The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar metho...The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar method and Coats-Redfern method to fit various solid-state reaction models, and to achieve kinetic parameters of desolvation. The mechanism of thermal desolvation was evaluated using the kinetic compensation effect. The results show that kinetics of desolvation of erythromycin acetone solvate was compatible with the mechanism of a two-dimensional diffusion controlled and was best expressed by Valensi equation. Corresponding to the integral method and the differential method, the activation energy of desolvation of erythromycin acetone solvate was estimated to be 51.26—57.11 kJ/mol, and the pre-exponential factor was 8.077×106 s-1—4.326×107 s-1, respectively.展开更多
The glycation of hemoglobin is catalyzed by buffer phosphate and arsenate. The catalytic constant (kB) for aqueous arsenate is two-fold larger than for aqueous phosphate. The catalytic constant (ks) of phosphate i...The glycation of hemoglobin is catalyzed by buffer phosphate and arsenate. The catalytic constant (kB) for aqueous arsenate is two-fold larger than for aqueous phosphate. The catalytic constant (ks) of phosphate in sorbitol mixtures increase from (1.67 ± 0.11) × 10-10 s-1·M-1 to (5.78 ± 0.39) × 10-10 s-1·M-1 and the catalytic constant is enhanced 3.5 times, relative to that in water; the catalytic constant (kB) of arsenate in sorbitol mixtures increase from (2.98±0.07)× 10-10 s-1·M-1 to (6.62 ± 0.53) × 10-10 s-1·M-1 and the catalytic constant is enhanced 2 times, relative to that in water. The spontaneous rate constants are independent of sorbitol concentration for phosphate and arsenate. The catalytic power of phosphate and arsenate in sorbitol are the same. Desolvation of strongly hydrated species such as HPO42 and HAsO42 should make a contribution to the energy cost of the formation of anion-hemoglobin complexes and can be a possible explanation for higher catalytic potential of HAsO42 in water. The same catalytic constant (ksB) for phosphate and arsenate in sorbitol indicates that the same catalyst base group on the hemoglobin molecule may be involved in the abstraction of proton in the Amadori rearrangement.展开更多
Biomolecular self-assembly based on peptides and proteins is a general phenomenon encountered in natural and synthetic systems.Liquid–liquid phase separation(LLPS)is intimately involved in biomolecular self-assembly,...Biomolecular self-assembly based on peptides and proteins is a general phenomenon encountered in natural and synthetic systems.Liquid–liquid phase separation(LLPS)is intimately involved in biomolecular self-assembly,yet the key factors at a molecular scale activating or modulating such a process remain largely elusive.Herein,we discovered in our experiments that multistep desolvation is fundamental to the formation and evolution of peptide-rich droplets:The first step was partial desolvation of peptides to form peptide clusters,and the second step was selective desolvation of hydrophobic groups within clusters to trigger LLPS and the formation of peptiderich droplets,followed by complete desolvation of droplets,initiating the nucleation of peptide selfassembly.Manipulation of the degree of desolvation at different stages was an effective strategy to control the self-assembly pathways and polymorphisms.This study sheds light on the molecular origin of LLPS-mediated self-assembly distinct from classical one-step self-assembly and paves the way for the precise control of supramolecular self-assembly.展开更多
Achieving a highly robust zinc(Zn)metal anode is extremely important for improving the performance of aqueous Zn-ion batteries(AZIBs)for advancing“carbon neutrality”society,which is hampered by the uncontrollable gr...Achieving a highly robust zinc(Zn)metal anode is extremely important for improving the performance of aqueous Zn-ion batteries(AZIBs)for advancing“carbon neutrality”society,which is hampered by the uncontrollable growth of Zn dendrite and severe side reactions including hydrogen evolution reaction,corrosion,and passivation,etc.Herein,an interlayer containing fluorinated zincophilic covalent organic framework with sulfonic acid groups(COF-S-F)is developed on Zn metal(Zn@COF-S-F)as the artificial solid electrolyte interface(SEI).Sulfonic acid group(-SO_(3)H)in COF-S-F can effectively ameliorate the desolvation process of hydrated Zn ions,and the three-dimensional channel with fluoride group(-F)can provide interconnected channels for the favorable transport of Zn ions with ion-confinement effects,endowing Zn@COF-S-F with dendrite-free morphology and suppressed side reactions.Consequently,Zn@COF-S-F symmetric cell can stably cycle for 1,000 h with low average hysteresis voltage(50.5 m V)at the current density of 1.5 m A cm^(-2).Zn@COF-S-F|Mn O_(2)cell delivers the discharge specific capacity of 206.8 m Ah g^(-1)at the current density of 1.2 A g^(-1)after 800 cycles with high-capacity retention(87.9%).Enlightening,building artificial SEI on metallic Zn surface with targeted design has been proved as the effective strategy to foster the practical application of high-performance AZIBs.展开更多
Zinc metal anodes are gaining popularity in aqueous electrochemical energy storage systems for their high safety,cost-effectiveness,and high capacity.However,the service life of zinc metal anodes is severely constrain...Zinc metal anodes are gaining popularity in aqueous electrochemical energy storage systems for their high safety,cost-effectiveness,and high capacity.However,the service life of zinc metal anodes is severely constrained by critical challenges,including dendrites,water-induced hydrogen evolution,and passivation.In this study,a protective two-dimensional metal–organic framework interphase is in situ constructed on the zinc anode surface with a novel gel vapor deposition method.The ultrathin interphase layer(~1μm)is made of layer-stacking 2D nanosheets with angstrom-level pores of around 2.1Å,which serves as an ion sieve to reject large solvent–ion pairs while homogenizes the transport of partially desolvated zinc ions,contributing to a uniform and highly reversible zinc deposition.With the shielding of the interphase layer,an ultra-stable zinc plating/stripping is achieved in symmetric cells with cycling over 1000 h at 0.5 mA cm−2 and~700 h at 1 mA cm^(−2),far exceeding that of the bare zinc anodes(250 and 70 h).Furthermore,as a proof-of-concept demonstration,the full cell paired with MnO_(2) cathode demonstrates improved rate performances and stable cycling(1200 cycles at 1 A g−1).This work provides fresh insights into interphase design to promote the performance of zinc metal anodes.展开更多
Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferio...Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs.展开更多
Stibium(Sb)metal with high theoretic capacity,suitable negative working window and inexpensive nature are promising anode material for advanced aqueous alkaline batteries(AABs).However,the further development of Sb an...Stibium(Sb)metal with high theoretic capacity,suitable negative working window and inexpensive nature are promising anode material for advanced aqueous alkaline batteries(AABs).However,the further development of Sb anode is severely hindered by the low capacity and poor rate capability which is originated from deficient adsorption of[Sb(OH)_(4)]^(-)and its sluggish desolvation kinetics.Herein,a nitrogen doped carbon cages(NCCs)substrate is constructed as high capacity and rate capability anode by promoting the adsorption and following desolvation process of[Sb(OH)_(4)]^(-)via the enhanced attraction toward(OH)-in the solvated[Sb(OH)_(4)]^(-).Consequently,the designed Sb/NCCs anode delivers a high capacity of 627 m Ah g^(-1)with an average 95%Sb utilization,an outstanding coulombic efficiency(CE)of 95%and an impressive lifespan(>110 h).Meanwhile,the Ni_(3)Se_(2)//Sb/NCCs batteries show great capacity retention of 86.7%after 2000 cycles with an areal capacity of 0.52 m Ah cm^(-2).Implementation of the designed anode allows for the construction of Sb-based AABs with enhanced rate capability,energy density and cycling performance.展开更多
Diffusion reaction of the labile building block Mg(acacCN)2 (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)aAg...Diffusion reaction of the labile building block Mg(acacCN)2 (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)aAg].solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)aAg]-4CHCl3 in space group P]- is obtained as platelet-shaped crystals from a mixture of methanol and chloroform. When kept in the reaction mixture, these thin plates within one week convert to isometric tetrahedral crystals of the 3D network [Mg(acacCN)3Ag]. 2CHC13 in the cubic space group/9213. The transformation reaction proceeds via dissolution and recrystallization. The co-crystallized solvent molecules play an important role for stabilizing the target structure: They subtend Cl...Cl contacts and interact via non- classical C-H.-. O hydrogen bonds with the coordination framework. In the new cubic coordination network, both Mg(II) and Ag(I) adopt octahedral coordination, with unprecedented face-sharing by bridging O atoms of three acetylacetonato moieties. Prolonged standing of [Mg(acacCN)3Ag]-2CHCl3 in the reaction medium leads to further degradation, under formation of [Ag(acacCN)].展开更多
High interfacial energy Li^(0)-electrolyte interface contributes to larger Li^(0) nucleation embryos and a more stable interface,so the interfacial energy is essential for highly reversible Li^(0) deposition/stripping...High interfacial energy Li^(0)-electrolyte interface contributes to larger Li^(0) nucleation embryos and a more stable interface,so the interfacial energy is essential for highly reversible Li^(0) deposition/stripping.Herein,a high interfacial-energy artificial solid electrolyte interphase(SEI)with rich LiF embedded in lithiated poly-2-acrylamido-2-methylpropane sulfonic acid(PAMPS-Li)network is designed to realize favorable Li^(0) nucleation and rapid desolvation of Li+simultaneously.The Li-F bonds in LiF(001)exhibit stronger ion-dipole interactions with Li atoms,offering higher interfacial energies.When the growth surface energy and total interfacial energy of Li^(0) are balanced,the high interfacial energy SEI with abundant LiF can promote the formation of larger Li^(0) nucleation embryos.In addition,the PAMPS-Li with immobilized anions presents weaker interaction with Li^(0) and possesses higher polymer-Li interfacial energy,and its amide and sulfonic acid groups exhibit higher binding energies with Li^(+).Therefore,PAMPS-Li can easily promote the Li+to escape from the solvent sheath and weaken the desolvation energy barrier.The highly reversible Li^(0) deposition behavior with restricted side reactions is achieved based on the synergistic modification of high interfacial energy SEI with heterostructure.Most importantly,lifespan of multi-layered Li^(0) pouch cell(330 Wh kg-1)with a low N/P ratio(1.67)is over 100 cycles,verifying its potential practical application.展开更多
The practical application of Li metal anodes(LMAs)is limited by uncontrolled dendrite growth and side reactions.Herein,we propose a new friction-induced strategy to produce high-performance thin Li anode(Li@CFO).By vi...The practical application of Li metal anodes(LMAs)is limited by uncontrolled dendrite growth and side reactions.Herein,we propose a new friction-induced strategy to produce high-performance thin Li anode(Li@CFO).By virtue of the in situ friction reaction between fluoropolymer grease and Li strips during rolling,a robust organic/inorganic hybrid interlayer(lithiophilic LiF/LiC_(6)framework hybridized-CF_(2)-O-CF_(2)-chains)was formed atop Li metal.The derived interface contributes to reversible Li plating/stripping behaviors by mitigating side reactions and decreasing the solvation degree at the interface.The Li@CFO||Li@CFO symmetrical cell exhibits a remarkable lifespan for 5,600 h(1.0 mA cm^(-2)and 1.0 mAh cm^(-2))and 1,350 cycles even at a harsh condition(18.0 mA cm^(-2)and 3.0 mAh cm^(-2)).When paired with high-loading LiFePO4 cathodes,the full cell lasts over 450 cycles at 1C with a high-capacity retention of 99.9%.This work provides a new friction-induced strategy for producing high-performance thin LMAs.展开更多
Self-charging power systems collecting energy harvesting technology and batteries are attracting extensive attention.To solve the disadvantages of the traditional integrated system,such as highly dependent on energy s...Self-charging power systems collecting energy harvesting technology and batteries are attracting extensive attention.To solve the disadvantages of the traditional integrated system,such as highly dependent on energy supply and complex structure,an airrechargeable Zn battery based on MoS_(2)/PANI cathode is reported.Benefited from the excellent conductivity desolvation shield of PANI,the MoS_(2)/PANI cathode exhibits ultra-high capacity(304.98 mAh g^(−1) in N_(2) and 351.25 mAh g^(−1) in air).In particular,this battery has the ability to collect,convert and store energy simultaneously by an airrechargeable process of the spontaneous redox reaction between the discharged cathode and O2 from air.The air-rechargeable Zn batteries display a high open-circuit voltage(1.15 V),an unforgettable discharge capacity(316.09 mAh g^(−1) and the air-rechargeable depth is 89.99%)and good air-recharging stability(291.22 mAh g^(−1) after 50 air recharging/galvanostatic current discharge cycle).Most importantly,both our quasi-solid zinc ion batteries and batteries modules have excellent performance and practicability.This work will provide a promising research direction for the material design and device assembly of the next-generation self-powered system.展开更多
Determination of thirty four trace metal elements in electronic high purity hydrochloric acid by ICP-MS (Standard Condition, Plasma Screen Condition) with membrane desolvation was described. Matrix effects were compen...Determination of thirty four trace metal elements in electronic high purity hydrochloric acid by ICP-MS (Standard Condition, Plasma Screen Condition) with membrane desolvation was described. Matrix effects were compensated by adding rhodium as the internal standard. Detection limits is 0.1 to 100 ng/L; the recovery of the method is 90%-110%. Long term RSD was less than 5%. The results from ICP and ICP-MS are correspondent. ICP-MS improves the accuracy and efficiency of analyses.展开更多
This article focuses on iodine determination by microwave plasma torch atomic emission spectrometry (MPT-AES) coupled with online preconcentration vapor generation method. A new desolvation device, multistrand Nafio...This article focuses on iodine determination by microwave plasma torch atomic emission spectrometry (MPT-AES) coupled with online preconcentration vapor generation method. A new desolvation device, multistrand Nafion dryer, was used as the substitute for condenser desolvation system. Some experimental conditions, such as preconcentration time, acidity of sample solution, rinsing solution acidity and dynamic linear range were investigated and optimized. The new desolvation system eliminates the problem of decreasing emission intensity of I(I) 206.238 nm line with the increase of working time on a conventional condenser desolvation system, thus greatly improving the reproducibility.展开更多
Lithium-sulfur(Li-S)batteries mainly rely on the reversible electrochemical reaction of between lithium ions(Li^(+))and sulfur species to achieve energy storage and conversion,therefore,increasing the number of free L...Lithium-sulfur(Li-S)batteries mainly rely on the reversible electrochemical reaction of between lithium ions(Li^(+))and sulfur species to achieve energy storage and conversion,therefore,increasing the number of free Li^(+)and improving the Li^(+)diffusion kinetics will effectively enhance the cell performance.Here,Mo-based MXene heterostructure(MoS_(2)@Mo_(2)C)was developed by partial vulcanization of Mo_(2)C MXene,in which the introduction of similar valence S into Mo-based MXene(Mo_(2)C)can create an electron delocalization effect.Through theoretical simulations and electrochemical characterisation,it is demonstrated that the MoS_(2)@Mo_(2)C heterojunction can effectively promote ion desolvation,increase the amount of free Li^(+),and accelerate Li^(+)transport for more efficient polysulfide conversion.In addition,the MoS_(2)@Mo_(2)C material is also capable of accelerating the oxidation and reduction of polysulfides through its sufficient defects and vacancies to further enhance the catalytic efficiency.Consequently,the Li-S battery with the designed MoS_(2)@Mo_(2)C electrocatalyst performed for 500 cycles at 1 C and still maintained the ideal capacity(664.7 mAh·g^(−1)),and excellent rate performance(567.6 mAh·g^(−1)at 5 C).Under the extreme conditions of high loading,the cell maintained an excellent capacity of 775.6 mAh·g^(−1)after 100 cycles.It also retained 838.4 mAh·g^(−1)for 70 cycles at a low temperature of 0℃,and demonstrated a low decay rate(0.063%).These results indicate that the delocalized electrons effectively accelerate the catalytic conversion of lithium polysulfide,which is more practical for enhancing the behaviour of Li-S batteries.展开更多
Chemical prelithiation is widely proven to be an effective strategy to address the low initial coulombic efficiency(ICE)of promising SiO_(x) anode.Though the reagent composition has been widely explored,the Li^(+) sol...Chemical prelithiation is widely proven to be an effective strategy to address the low initial coulombic efficiency(ICE)of promising SiO_(x) anode.Though the reagent composition has been widely explored,the Li^(+) solvation structure,which practically plays the cornerstone role in the prelithiation ability,rate,uniformility,has rarely been explored.A novel environmentally-friendly reagent with weak solvent cyclopentyl methyl ether(CPME)is proposed that enables both improved ICE and spatial homogeneous solid electrolyte interphase(SEl).And the prelithiation behavior and mechanism were explored focused on the Li^(+) solvation structure.Both theoretical investigation and spectroscopic results suggest that weak solvent feature of CPME reduces the solvent coordination number and decreases the Li^(+) desolvation energy.展开更多
Lithium-metal batteries with high energy/power densities have significant applications in electronics,electric vehicles,and stationary power plants.However,the unstable lithium-metal-anode/electrolyte interface has in...Lithium-metal batteries with high energy/power densities have significant applications in electronics,electric vehicles,and stationary power plants.However,the unstable lithium-metal-anode/electrolyte interface has induced insufficient cycle life and safety issues.To improve the cycle life and safety,understanding the formation of the solid electrolyte interphase(SEI)and growth of lithium dendrites near the anode/electrolyte interface,regulating the electrodeposition/electrostripping processes of Li^(+),and developing multiple approaches for protecting the lithium-metal surface and SEI layer are crucial and necessary.This paper comprehensively reviews the research progress in SEI and lithium dendrite growth in terms of their classical electrochemical lithium plating/stripping processes,interface interaction/nucleation processes,anode geometric evolution,fundamental electrolyte reduction mechanisms,and effects on battery performance.Some important aspects,such as charge transfer,the local current distribution,solvation,desolvation,ion diffusion through the interface,inhibition of dendrites by the SEI,additives,models for dendrite formation,heterogeneous nucleation,asymmetric processes during stripping/plating,the host matrix,and in situ nucleation characterization,are also analyzed based on experimental observations and theoretical calculations.Several technical challenges in improving SEI properties and reducing lithium dendrite growth are analyzed.Furthermore,possible future research directions for overcoming the challenges are also proposed to facilitate further research and development toward practical applications.展开更多
Fluorinated carbons(CF_(x))/Li primary batteries with high theoretical energy density have been applied as indispensable energy storage devices with no need for rechargeability,yet plagued by poor rate capability and ...Fluorinated carbons(CF_(x))/Li primary batteries with high theoretical energy density have been applied as indispensable energy storage devices with no need for rechargeability,yet plagued by poor rate capability and narrow temperature adaptability in actual scenarios.Herein,benefiting from precise solvation engineering for synergistic coordination of anions and low-affinity solvents,the optimized cyclic ether-based electrolyte is elaborated to significantly facilitate overall reaction dynamics closely correlated to lower desolvation barrier.As a result,the excellent rate(15 C,650 mAh g^(-1))at room-temperature and ultra-lowtemperature performance dropping to-80°C(495 mAh g^(-1)at average output voltage of 2.11 V)is delivered by the end of 1.5 V cut-off voltage,far superior to other organic liquid electrolytes.Furthermore,the CF_(x)/Li cell employing the high-loading electrode(18-22 mg cm^(-2))still yields 1,683 and 1,395 Wh kg^(-1)in the case of-40°C and-60°C,respectively.In short,the novel design strategy for cyclic ethers as basic solvents is proposed to enable the CF_(x)/Li battery with superb subzero performances,which shows great potential in practical application for extreme environments.展开更多
The electrochemical performance of hard carbon(HC)materials is closely related to the electrolyte used in the sodium ion batteries(SIBs).Conventional electrolytes carbonate(EC)demonstrates low initial Columbic efficie...The electrochemical performance of hard carbon(HC)materials is closely related to the electrolyte used in the sodium ion batteries(SIBs).Conventional electrolytes carbonate(EC)demonstrates low initial Columbic efficiency(ICE)and poor rate performance,which is one of the main bottlenecks that limits the practical application of HCs.Ether electrolyte(diglyme)was reported to improve the rate performance of HCs.Nevertheless,the underlying mechanism for the excellent rate capability is still lack of in-depth study.In this work,the differences of sodium-ion diffusion between ether and carbonate-base electrolytes in HCs are analyzed layer by layer.Firstly,when sodium-ions are diffused in electrolyte,the diffusion coefficient of sodium-ion in ether electrolyte is about 2.5 times higher than that in ester electrolytes by molecular dynamics(MD)simulation and experimental characterization.Furthermore,when the solvated sodium-ions are diffused into the solid electrolyte interphase(SEI)interface and the HCs material,the enhanced charge transfer kinetics(thin SEI layer(4.6 vs.12 nm)and low RSEI(1.5 vs.24Ω))at the SEI combined with low desolvation energy(0.248 eV)are responsible for high-rate performance and good cycling stability of HC in ether electrolyte.Therefore,high diffusion coefficient,low desolvation energy,and good interface are the intrinsic reasons for enhanced rate performance in ether electrolyte,which also has guiding significance for the design of other high-rate electrolytes.展开更多
Cation exchange(CE)has been emerged as a promising post-synthesis strategy of colloidal nanocrystals.However,it is unclear how the cation precursor affects the CE process and the final colloidal nanocrystals.Herein,we...Cation exchange(CE)has been emerged as a promising post-synthesis strategy of colloidal nanocrystals.However,it is unclear how the cation precursor affects the CE process and the final colloidal nanocrystals.Herein,we utilized two Zn-B Lewis acidbase adduct complexes(B=oleylamine(OAM)and methanol(MeOH))as Zn precursors for CE with Ag_(2)S quantum dots(QDs).Our study revealed that the steric hindrance and complexing capabilities of Zn precursor significantly affect the CE kinetics.As a result,the Zn-doped Ag_(2)S(Zn:Ag_(2)S)and Ag_(2)S@ZnS core–shell QDs were successfully obtained with enormous enhancement of their photoluminescence(PL)intensities.Theoretical simulation showed that the Zn-OAM with higher desolvation energy and spatial hindrance tended to form doped Zn:Ag_(2)S QDs due to the inefficient cation exchange.Whereas the Zn-MeOH with lower exchange barrier promoted the conversion of Ag-S to Zn-S,thus forming Ag_(2)S@ZnS core–shell QDs.We anticipate that this finding will enrich the regulatory approaches of post-synthesis of colloidal nanocrystals with desirable properties.展开更多
Li^(+) solvation structures have a decisive influence on the electrode/electrolyte interfacial properties and battery performances.Reduced salt concentration may result in an organic rich solid electrolyte interface(S...Li^(+) solvation structures have a decisive influence on the electrode/electrolyte interfacial properties and battery performances.Reduced salt concentration may result in an organic rich solid electrolyte interface(SEI)and catastrophic cycle stability,which makes low concentration electrolytes(LCEs)rather challenging.Solvents with low solvating power bring in new chances to LCEs due to the weak salt-solvent interactions.Herein,an LCE with only 0.25 mol L^(-1) salt is prepared with fluoroethylene carbonate(FEC)and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether(D_(2)).Molecular dynamics simulations and experiments prove that the low solvating power solvent FEC not only renders reduced desolvation energy to Li^(+) and improves the battery kinetics,but also promotes the formation of a LiF-rich SEI that hinders the electrolyte consumption.Li||Cu cell using the LCE shows a high coulombic efficiency of 99.20%,and LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)||Li cell also exhibits satisfying capacity retention of 89.93%in 200 cycles,which demonstrates the great potential of solvating power regulation in LCEs development.展开更多
文摘The desolvation of erythromycin acetone solvate was investigated under non-isothermal conditions by a thermogravimetric analyzer. This paper emphasized the kinetic analysis of non-isothermal TG-DTA data by Achar method and Coats-Redfern method to fit various solid-state reaction models, and to achieve kinetic parameters of desolvation. The mechanism of thermal desolvation was evaluated using the kinetic compensation effect. The results show that kinetics of desolvation of erythromycin acetone solvate was compatible with the mechanism of a two-dimensional diffusion controlled and was best expressed by Valensi equation. Corresponding to the integral method and the differential method, the activation energy of desolvation of erythromycin acetone solvate was estimated to be 51.26—57.11 kJ/mol, and the pre-exponential factor was 8.077×106 s-1—4.326×107 s-1, respectively.
文摘The glycation of hemoglobin is catalyzed by buffer phosphate and arsenate. The catalytic constant (kB) for aqueous arsenate is two-fold larger than for aqueous phosphate. The catalytic constant (ks) of phosphate in sorbitol mixtures increase from (1.67 ± 0.11) × 10-10 s-1·M-1 to (5.78 ± 0.39) × 10-10 s-1·M-1 and the catalytic constant is enhanced 3.5 times, relative to that in water; the catalytic constant (kB) of arsenate in sorbitol mixtures increase from (2.98±0.07)× 10-10 s-1·M-1 to (6.62 ± 0.53) × 10-10 s-1·M-1 and the catalytic constant is enhanced 2 times, relative to that in water. The spontaneous rate constants are independent of sorbitol concentration for phosphate and arsenate. The catalytic power of phosphate and arsenate in sorbitol are the same. Desolvation of strongly hydrated species such as HPO42 and HAsO42 should make a contribution to the energy cost of the formation of anion-hemoglobin complexes and can be a possible explanation for higher catalytic potential of HAsO42 in water. The same catalytic constant (ksB) for phosphate and arsenate in sorbitol indicates that the same catalyst base group on the hemoglobin molecule may be involved in the abstraction of proton in the Amadori rearrangement.
基金supported by the National Science Fund for Distinguished Young Scholars of China(grant no.22025207)National Natural Science Foundation of China(grant nos.22172172 and 22232006)+3 种基金Youth Innovation Promotion Association of CAS(grant no.2022049)China Scholarship Council(CSC,grant no.202104910187)IPE Project for Frontier Basic Research(grant no.QYJC-2022-011)Natural Science Foundation of Hebei Province(grant nos.B2020103036 and B2020103025).
文摘Biomolecular self-assembly based on peptides and proteins is a general phenomenon encountered in natural and synthetic systems.Liquid–liquid phase separation(LLPS)is intimately involved in biomolecular self-assembly,yet the key factors at a molecular scale activating or modulating such a process remain largely elusive.Herein,we discovered in our experiments that multistep desolvation is fundamental to the formation and evolution of peptide-rich droplets:The first step was partial desolvation of peptides to form peptide clusters,and the second step was selective desolvation of hydrophobic groups within clusters to trigger LLPS and the formation of peptiderich droplets,followed by complete desolvation of droplets,initiating the nucleation of peptide selfassembly.Manipulation of the degree of desolvation at different stages was an effective strategy to control the self-assembly pathways and polymorphisms.This study sheds light on the molecular origin of LLPS-mediated self-assembly distinct from classical one-step self-assembly and paves the way for the precise control of supramolecular self-assembly.
基金financially supported by National Natural Science Foundation of China(Nos.51872090,51772097,52372252)Hebei Natural Science Fund for Distinguished Young Scholar(No.E2019209433)+1 种基金Youth Talent Program of Hebei Provincial Education Department(No.BJ2018020)Natural Science Foundation of Hebei Province(No.E2020209151)。
文摘Achieving a highly robust zinc(Zn)metal anode is extremely important for improving the performance of aqueous Zn-ion batteries(AZIBs)for advancing“carbon neutrality”society,which is hampered by the uncontrollable growth of Zn dendrite and severe side reactions including hydrogen evolution reaction,corrosion,and passivation,etc.Herein,an interlayer containing fluorinated zincophilic covalent organic framework with sulfonic acid groups(COF-S-F)is developed on Zn metal(Zn@COF-S-F)as the artificial solid electrolyte interface(SEI).Sulfonic acid group(-SO_(3)H)in COF-S-F can effectively ameliorate the desolvation process of hydrated Zn ions,and the three-dimensional channel with fluoride group(-F)can provide interconnected channels for the favorable transport of Zn ions with ion-confinement effects,endowing Zn@COF-S-F with dendrite-free morphology and suppressed side reactions.Consequently,Zn@COF-S-F symmetric cell can stably cycle for 1,000 h with low average hysteresis voltage(50.5 m V)at the current density of 1.5 m A cm^(-2).Zn@COF-S-F|Mn O_(2)cell delivers the discharge specific capacity of 206.8 m Ah g^(-1)at the current density of 1.2 A g^(-1)after 800 cycles with high-capacity retention(87.9%).Enlightening,building artificial SEI on metallic Zn surface with targeted design has been proved as the effective strategy to foster the practical application of high-performance AZIBs.
基金supported by the grants from the Research Grants Council of the Hong Kong Special Administrative Region,China(Project No.C5031-20)the Guangdong Major Project of Basic and Applied Basic Research(2023B0303000002).
文摘Zinc metal anodes are gaining popularity in aqueous electrochemical energy storage systems for their high safety,cost-effectiveness,and high capacity.However,the service life of zinc metal anodes is severely constrained by critical challenges,including dendrites,water-induced hydrogen evolution,and passivation.In this study,a protective two-dimensional metal–organic framework interphase is in situ constructed on the zinc anode surface with a novel gel vapor deposition method.The ultrathin interphase layer(~1μm)is made of layer-stacking 2D nanosheets with angstrom-level pores of around 2.1Å,which serves as an ion sieve to reject large solvent–ion pairs while homogenizes the transport of partially desolvated zinc ions,contributing to a uniform and highly reversible zinc deposition.With the shielding of the interphase layer,an ultra-stable zinc plating/stripping is achieved in symmetric cells with cycling over 1000 h at 0.5 mA cm−2 and~700 h at 1 mA cm^(−2),far exceeding that of the bare zinc anodes(250 and 70 h).Furthermore,as a proof-of-concept demonstration,the full cell paired with MnO_(2) cathode demonstrates improved rate performances and stable cycling(1200 cycles at 1 A g−1).This work provides fresh insights into interphase design to promote the performance of zinc metal anodes.
基金supported by the National Natural Science Foundation of China(Nos.21975087,22008082)。
文摘Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(No.2019A1515110538)Dongguan Science and Technology of Social Development Program(No.20211800904642)+2 种基金the open research fund of Guangdong Provincial Key Laboratory of Distributed Energy Systems(No.2020DES2)Joint Science Foundation of Wuyi University and HK and Macao(2019WGALH14)Guangdong province innovation and strong school project(2020ZDZX2004)。
文摘Stibium(Sb)metal with high theoretic capacity,suitable negative working window and inexpensive nature are promising anode material for advanced aqueous alkaline batteries(AABs).However,the further development of Sb anode is severely hindered by the low capacity and poor rate capability which is originated from deficient adsorption of[Sb(OH)_(4)]^(-)and its sluggish desolvation kinetics.Herein,a nitrogen doped carbon cages(NCCs)substrate is constructed as high capacity and rate capability anode by promoting the adsorption and following desolvation process of[Sb(OH)_(4)]^(-)via the enhanced attraction toward(OH)-in the solvated[Sb(OH)_(4)]^(-).Consequently,the designed Sb/NCCs anode delivers a high capacity of 627 m Ah g^(-1)with an average 95%Sb utilization,an outstanding coulombic efficiency(CE)of 95%and an impressive lifespan(>110 h).Meanwhile,the Ni_(3)Se_(2)//Sb/NCCs batteries show great capacity retention of 86.7%after 2000 cycles with an areal capacity of 0.52 m Ah cm^(-2).Implementation of the designed anode allows for the construction of Sb-based AABs with enhanced rate capability,energy density and cycling performance.
文摘Diffusion reaction of the labile building block Mg(acacCN)2 (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)aAg].solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)aAg]-4CHCl3 in space group P]- is obtained as platelet-shaped crystals from a mixture of methanol and chloroform. When kept in the reaction mixture, these thin plates within one week convert to isometric tetrahedral crystals of the 3D network [Mg(acacCN)3Ag]. 2CHC13 in the cubic space group/9213. The transformation reaction proceeds via dissolution and recrystallization. The co-crystallized solvent molecules play an important role for stabilizing the target structure: They subtend Cl...Cl contacts and interact via non- classical C-H.-. O hydrogen bonds with the coordination framework. In the new cubic coordination network, both Mg(II) and Ag(I) adopt octahedral coordination, with unprecedented face-sharing by bridging O atoms of three acetylacetonato moieties. Prolonged standing of [Mg(acacCN)3Ag]-2CHCl3 in the reaction medium leads to further degradation, under formation of [Ag(acacCN)].
基金supported by the National Natural Science Foundation of China(22109030 and 21875195)Guangdong Basic and Applied Basic Research Foundation(2019A1515111069 and 2021A1515010177)the Key Research and Development Program of Yunnan Province(202103AA080019)。
文摘High interfacial energy Li^(0)-electrolyte interface contributes to larger Li^(0) nucleation embryos and a more stable interface,so the interfacial energy is essential for highly reversible Li^(0) deposition/stripping.Herein,a high interfacial-energy artificial solid electrolyte interphase(SEI)with rich LiF embedded in lithiated poly-2-acrylamido-2-methylpropane sulfonic acid(PAMPS-Li)network is designed to realize favorable Li^(0) nucleation and rapid desolvation of Li+simultaneously.The Li-F bonds in LiF(001)exhibit stronger ion-dipole interactions with Li atoms,offering higher interfacial energies.When the growth surface energy and total interfacial energy of Li^(0) are balanced,the high interfacial energy SEI with abundant LiF can promote the formation of larger Li^(0) nucleation embryos.In addition,the PAMPS-Li with immobilized anions presents weaker interaction with Li^(0) and possesses higher polymer-Li interfacial energy,and its amide and sulfonic acid groups exhibit higher binding energies with Li^(+).Therefore,PAMPS-Li can easily promote the Li+to escape from the solvent sheath and weaken the desolvation energy barrier.The highly reversible Li^(0) deposition behavior with restricted side reactions is achieved based on the synergistic modification of high interfacial energy SEI with heterostructure.Most importantly,lifespan of multi-layered Li^(0) pouch cell(330 Wh kg-1)with a low N/P ratio(1.67)is over 100 cycles,verifying its potential practical application.
基金This work was supported by the National Natural Science Foundation of China(U1904216 and U22A20141)the Natural Science Foundation of Changsha City(kq2208258).
文摘The practical application of Li metal anodes(LMAs)is limited by uncontrolled dendrite growth and side reactions.Herein,we propose a new friction-induced strategy to produce high-performance thin Li anode(Li@CFO).By virtue of the in situ friction reaction between fluoropolymer grease and Li strips during rolling,a robust organic/inorganic hybrid interlayer(lithiophilic LiF/LiC_(6)framework hybridized-CF_(2)-O-CF_(2)-chains)was formed atop Li metal.The derived interface contributes to reversible Li plating/stripping behaviors by mitigating side reactions and decreasing the solvation degree at the interface.The Li@CFO||Li@CFO symmetrical cell exhibits a remarkable lifespan for 5,600 h(1.0 mA cm^(-2)and 1.0 mAh cm^(-2))and 1,350 cycles even at a harsh condition(18.0 mA cm^(-2)and 3.0 mAh cm^(-2)).When paired with high-loading LiFePO4 cathodes,the full cell lasts over 450 cycles at 1C with a high-capacity retention of 99.9%.This work provides a new friction-induced strategy for producing high-performance thin LMAs.
基金supported by the National Natural Science Foundation of China(No.12274151)。
文摘Self-charging power systems collecting energy harvesting technology and batteries are attracting extensive attention.To solve the disadvantages of the traditional integrated system,such as highly dependent on energy supply and complex structure,an airrechargeable Zn battery based on MoS_(2)/PANI cathode is reported.Benefited from the excellent conductivity desolvation shield of PANI,the MoS_(2)/PANI cathode exhibits ultra-high capacity(304.98 mAh g^(−1) in N_(2) and 351.25 mAh g^(−1) in air).In particular,this battery has the ability to collect,convert and store energy simultaneously by an airrechargeable process of the spontaneous redox reaction between the discharged cathode and O2 from air.The air-rechargeable Zn batteries display a high open-circuit voltage(1.15 V),an unforgettable discharge capacity(316.09 mAh g^(−1) and the air-rechargeable depth is 89.99%)and good air-recharging stability(291.22 mAh g^(−1) after 50 air recharging/galvanostatic current discharge cycle).Most importantly,both our quasi-solid zinc ion batteries and batteries modules have excellent performance and practicability.This work will provide a promising research direction for the material design and device assembly of the next-generation self-powered system.
文摘Determination of thirty four trace metal elements in electronic high purity hydrochloric acid by ICP-MS (Standard Condition, Plasma Screen Condition) with membrane desolvation was described. Matrix effects were compensated by adding rhodium as the internal standard. Detection limits is 0.1 to 100 ng/L; the recovery of the method is 90%-110%. Long term RSD was less than 5%. The results from ICP and ICP-MS are correspondent. ICP-MS improves the accuracy and efficiency of analyses.
基金the Key Project for Science and Technology Development of Jilin Province, China(No.20010306-1)the China’s Post-doctoral Science Fund(No.20040350561).
文摘This article focuses on iodine determination by microwave plasma torch atomic emission spectrometry (MPT-AES) coupled with online preconcentration vapor generation method. A new desolvation device, multistrand Nafion dryer, was used as the substitute for condenser desolvation system. Some experimental conditions, such as preconcentration time, acidity of sample solution, rinsing solution acidity and dynamic linear range were investigated and optimized. The new desolvation system eliminates the problem of decreasing emission intensity of I(I) 206.238 nm line with the increase of working time on a conventional condenser desolvation system, thus greatly improving the reproducibility.
基金supported by the National Natural Science Foundation of China(No.U1710252)the Natural Science Foundation of Jiangsu Province(BK.20210130)+3 种基金Innovative and Entrepreneurial Doctor in Jiangsu Province(No.JSSCBS20211428)China Postdoctoral Science Foundation(No.2023M731084)Shanghai Sailing Program of China(No.23YF1408900)the Fundamental Research Funds for the Central Universities(No.JKD01231701).
文摘Lithium-sulfur(Li-S)batteries mainly rely on the reversible electrochemical reaction of between lithium ions(Li^(+))and sulfur species to achieve energy storage and conversion,therefore,increasing the number of free Li^(+)and improving the Li^(+)diffusion kinetics will effectively enhance the cell performance.Here,Mo-based MXene heterostructure(MoS_(2)@Mo_(2)C)was developed by partial vulcanization of Mo_(2)C MXene,in which the introduction of similar valence S into Mo-based MXene(Mo_(2)C)can create an electron delocalization effect.Through theoretical simulations and electrochemical characterisation,it is demonstrated that the MoS_(2)@Mo_(2)C heterojunction can effectively promote ion desolvation,increase the amount of free Li^(+),and accelerate Li^(+)transport for more efficient polysulfide conversion.In addition,the MoS_(2)@Mo_(2)C material is also capable of accelerating the oxidation and reduction of polysulfides through its sufficient defects and vacancies to further enhance the catalytic efficiency.Consequently,the Li-S battery with the designed MoS_(2)@Mo_(2)C electrocatalyst performed for 500 cycles at 1 C and still maintained the ideal capacity(664.7 mAh·g^(−1)),and excellent rate performance(567.6 mAh·g^(−1)at 5 C).Under the extreme conditions of high loading,the cell maintained an excellent capacity of 775.6 mAh·g^(−1)after 100 cycles.It also retained 838.4 mAh·g^(−1)for 70 cycles at a low temperature of 0℃,and demonstrated a low decay rate(0.063%).These results indicate that the delocalized electrons effectively accelerate the catalytic conversion of lithium polysulfide,which is more practical for enhancing the behaviour of Li-S batteries.
基金supported by projects from the National Natural Science Foundation of China(No.U20A20145)State Key Laboratory of Polymer Materials Engineering(No.sklpme2020-3-02)+6 种基金Sichuan Provincial Department of Science and Technology(No.2020YFG0022,No.2022YFG0124)Dazhou Department of Science and Technology(No.21ZDYF0001)Guangyuan Department of Science and Technology(No.22ZDYF0047)Sichuan Province Science and Technology Achievement Transfer and Transformation Project(No.21ZHSF0111)2020 Strategic Cooperation Project between Sichuan University and Suining Municipal People's Government Government(No.20221500008704170)the Open Project of State Key Laboratory of Environment-friendly Energy.Materials(No.20KFHG07)Start-up funding of Chemistry and Chemical Engineering Guangdong Laboratory(No.2122010).
文摘Chemical prelithiation is widely proven to be an effective strategy to address the low initial coulombic efficiency(ICE)of promising SiO_(x) anode.Though the reagent composition has been widely explored,the Li^(+) solvation structure,which practically plays the cornerstone role in the prelithiation ability,rate,uniformility,has rarely been explored.A novel environmentally-friendly reagent with weak solvent cyclopentyl methyl ether(CPME)is proposed that enables both improved ICE and spatial homogeneous solid electrolyte interphase(SEl).And the prelithiation behavior and mechanism were explored focused on the Li^(+) solvation structure.Both theoretical investigation and spectroscopic results suggest that weak solvent feature of CPME reduces the solvent coordination number and decreases the Li^(+) desolvation energy.
基金supported primarily by the National Key Research and Development Program of China(2020YFA0710303)National Natural Science Foundation of China(No.22109025)Natural Science Foundation of Fujian Province,China(2021J05121).
文摘Lithium-metal batteries with high energy/power densities have significant applications in electronics,electric vehicles,and stationary power plants.However,the unstable lithium-metal-anode/electrolyte interface has induced insufficient cycle life and safety issues.To improve the cycle life and safety,understanding the formation of the solid electrolyte interphase(SEI)and growth of lithium dendrites near the anode/electrolyte interface,regulating the electrodeposition/electrostripping processes of Li^(+),and developing multiple approaches for protecting the lithium-metal surface and SEI layer are crucial and necessary.This paper comprehensively reviews the research progress in SEI and lithium dendrite growth in terms of their classical electrochemical lithium plating/stripping processes,interface interaction/nucleation processes,anode geometric evolution,fundamental electrolyte reduction mechanisms,and effects on battery performance.Some important aspects,such as charge transfer,the local current distribution,solvation,desolvation,ion diffusion through the interface,inhibition of dendrites by the SEI,additives,models for dendrite formation,heterogeneous nucleation,asymmetric processes during stripping/plating,the host matrix,and in situ nucleation characterization,are also analyzed based on experimental observations and theoretical calculations.Several technical challenges in improving SEI properties and reducing lithium dendrite growth are analyzed.Furthermore,possible future research directions for overcoming the challenges are also proposed to facilitate further research and development toward practical applications.
基金financially supported from the Natural Science Foundation of Jilin Province(20220508141RC)
文摘Fluorinated carbons(CF_(x))/Li primary batteries with high theoretical energy density have been applied as indispensable energy storage devices with no need for rechargeability,yet plagued by poor rate capability and narrow temperature adaptability in actual scenarios.Herein,benefiting from precise solvation engineering for synergistic coordination of anions and low-affinity solvents,the optimized cyclic ether-based electrolyte is elaborated to significantly facilitate overall reaction dynamics closely correlated to lower desolvation barrier.As a result,the excellent rate(15 C,650 mAh g^(-1))at room-temperature and ultra-lowtemperature performance dropping to-80°C(495 mAh g^(-1)at average output voltage of 2.11 V)is delivered by the end of 1.5 V cut-off voltage,far superior to other organic liquid electrolytes.Furthermore,the CF_(x)/Li cell employing the high-loading electrode(18-22 mg cm^(-2))still yields 1,683 and 1,395 Wh kg^(-1)in the case of-40°C and-60°C,respectively.In short,the novel design strategy for cyclic ethers as basic solvents is proposed to enable the CF_(x)/Li battery with superb subzero performances,which shows great potential in practical application for extreme environments.
基金supported by the National Natural Science Foundation of China(Nos.22179077,51774251,and 21908142)Shanghai Science and Technology Commission’s“2020 Science and Technology In-novation Action Plan”(No.20511104003)Natural Science Foundation in Shanghai(No.21ZR1424200).
文摘The electrochemical performance of hard carbon(HC)materials is closely related to the electrolyte used in the sodium ion batteries(SIBs).Conventional electrolytes carbonate(EC)demonstrates low initial Columbic efficiency(ICE)and poor rate performance,which is one of the main bottlenecks that limits the practical application of HCs.Ether electrolyte(diglyme)was reported to improve the rate performance of HCs.Nevertheless,the underlying mechanism for the excellent rate capability is still lack of in-depth study.In this work,the differences of sodium-ion diffusion between ether and carbonate-base electrolytes in HCs are analyzed layer by layer.Firstly,when sodium-ions are diffused in electrolyte,the diffusion coefficient of sodium-ion in ether electrolyte is about 2.5 times higher than that in ester electrolytes by molecular dynamics(MD)simulation and experimental characterization.Furthermore,when the solvated sodium-ions are diffused into the solid electrolyte interphase(SEI)interface and the HCs material,the enhanced charge transfer kinetics(thin SEI layer(4.6 vs.12 nm)and low RSEI(1.5 vs.24Ω))at the SEI combined with low desolvation energy(0.248 eV)are responsible for high-rate performance and good cycling stability of HC in ether electrolyte.Therefore,high diffusion coefficient,low desolvation energy,and good interface are the intrinsic reasons for enhanced rate performance in ether electrolyte,which also has guiding significance for the design of other high-rate electrolytes.
基金the National Key Research and Development Program of China(No.2021YFF0701804)the financial support from the National Natural Science Foundation of China(Nos.21934007,22001262,22177128,and 22271308)+1 种基金the Science and Technology Project of Suzhou(No.SZS201904)the Natural Science Foundation of Jiangsu Province(Nos.BK20222016,BK20200254,and BK20221262).
文摘Cation exchange(CE)has been emerged as a promising post-synthesis strategy of colloidal nanocrystals.However,it is unclear how the cation precursor affects the CE process and the final colloidal nanocrystals.Herein,we utilized two Zn-B Lewis acidbase adduct complexes(B=oleylamine(OAM)and methanol(MeOH))as Zn precursors for CE with Ag_(2)S quantum dots(QDs).Our study revealed that the steric hindrance and complexing capabilities of Zn precursor significantly affect the CE kinetics.As a result,the Zn-doped Ag_(2)S(Zn:Ag_(2)S)and Ag_(2)S@ZnS core–shell QDs were successfully obtained with enormous enhancement of their photoluminescence(PL)intensities.Theoretical simulation showed that the Zn-OAM with higher desolvation energy and spatial hindrance tended to form doped Zn:Ag_(2)S QDs due to the inefficient cation exchange.Whereas the Zn-MeOH with lower exchange barrier promoted the conversion of Ag-S to Zn-S,thus forming Ag_(2)S@ZnS core–shell QDs.We anticipate that this finding will enrich the regulatory approaches of post-synthesis of colloidal nanocrystals with desirable properties.
基金supported by the National Key Research and Development Program of China(2019YFA0705603)the National Natural Science Foundation of China(22078341)+1 种基金the Natural Science Foundation of Hebei Province(B2020103028)financial support from York University。
文摘Li^(+) solvation structures have a decisive influence on the electrode/electrolyte interfacial properties and battery performances.Reduced salt concentration may result in an organic rich solid electrolyte interface(SEI)and catastrophic cycle stability,which makes low concentration electrolytes(LCEs)rather challenging.Solvents with low solvating power bring in new chances to LCEs due to the weak salt-solvent interactions.Herein,an LCE with only 0.25 mol L^(-1) salt is prepared with fluoroethylene carbonate(FEC)and 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropylether(D_(2)).Molecular dynamics simulations and experiments prove that the low solvating power solvent FEC not only renders reduced desolvation energy to Li^(+) and improves the battery kinetics,but also promotes the formation of a LiF-rich SEI that hinders the electrolyte consumption.Li||Cu cell using the LCE shows a high coulombic efficiency of 99.20%,and LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)||Li cell also exhibits satisfying capacity retention of 89.93%in 200 cycles,which demonstrates the great potential of solvating power regulation in LCEs development.