The practical applications of aqueous Zn metal batteries are currently restricted by the inherent drawbacks of Zn such as the hydrogen evolution reaction,sluggish kinetics,and dendrite formation.To address these probl...The practical applications of aqueous Zn metal batteries are currently restricted by the inherent drawbacks of Zn such as the hydrogen evolution reaction,sluggish kinetics,and dendrite formation.To address these problems,herein,a limitedly Zn-doped MgF_(2)interphase comprising an upper region of pure,porous MgF_(2)and a lower region of gradient Zn-doped MgF_(2)is achieved via radio frequency sputtering technique.The porous MgF_(2)region is a polar insulator whose high corrosion resistance facilitates the de-solvation of the solvated Zn ions and suppression of hydrogen evolution,resulting in Zn metal electrodes with a low interfacial resistance.The Zn-doped MgF_(2)region facilitates fast transfer kinetics and homogeneous deposition of Zn ions owing to the interfacial polarization between the Zn dopant and MgF_(2)matrix,and the high concentration of the Zn dopant on the surface of the metal substrate as fine nuclei.Consequently,a symmetric cell incorporating the proposed Zn metal exhibits low overpotentials of~27.2 and~99.7 mV without Zn dendrites over 250 to 8000 cycles at current densities of 1.0 and 10.0 mA cm−2,respectively.The developed Zn/MnO2 full cell exhibits superior capacity retentions of 97.5%and 84.0%with average Coulombic efficiencies of 99.96%after 1000 and 3000 cycles,respectively.展开更多
Perovskite BaTaO_(2) N(BTON) is one of the most promising photocatalysts for solar water splitting due to its wide visible-light absorption and suitable conduction/valence bands,but it still confronts the challenge of...Perovskite BaTaO_(2) N(BTON) is one of the most promising photocatalysts for solar water splitting due to its wide visible-light absorption and suitable conduction/valence bands,but it still confronts the challenge of high defect density causing decreased charge separation as well as photocatalytic activity.In this work,we develop a simple zinc doping strategy to greatly suppress its defect density and promote its water reduction performance.It is found that the defect formation on the nitrided Ba(Zn_(1/3-x)Ta_(2/3))O_(3-y)N_z(denoted as BZTON hereafter) will be greatly inhibited when the Zn-doped Ba(Zn_(1/3)Ta_(2/3))O_(3)(BZTO) oxide is used as the nitridation precursor.The structural characterizations and discussion demonstrate that the effective inhibition of Ta^(5+)into Ta^(4+)defects in BZTON mainly results from the easy reduction of zinc ions into metal and further the evaporation of zinc metal under the thermal ammonia flow.Interestingly,this simply doping methodology can be easily extended into the synthesis of SrTaO_(2) N(STON) with extremely low defect density,demonstrating its generality.Benefiting from the successful control to the defect density,the as-obtained BZTON photocatalyst exhibits remarkably promoted charge separation as well as water reduction activity to produce hydrogen with respect to the pristine BTON.Our work may provide an alternative avenue to prepare oxynitride semiconductors with reduced defect density for promoted solar energy conversion.展开更多
Aluminum doped zinc oxide （AZO）, as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that t...Aluminum doped zinc oxide （AZO）, as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that the rate performance and low-temperature performance of LiFePO4 are greatly improved by the surface treatment. Even at 20C rate, the discharge specific capacity of 100.9 mA.h/g was obtained by the AZO-coated LiFePO4 at room temperature. At -20 ℃, the discharge specific capacity at 0.2C for un-coated LiFePO4 and the coated one are 50.3 mA.h/g and 119.4 mA.h/g, respectively. It should be attributed to the electrically conductive AZO-coating which increases the electronic conductivity of LiFePO4. Furthermore, the surface-coating increases the tap-density of LiFePO4. The results indicate that the AZO-coated LiFePO4 is a good candidate of cathode material for applying in lithium power batteries.展开更多
In this study we used a chemical solution method from oxalic acid (OX. acid) and zinc acetate (ZnAc) to prepare Zinc Oxide nanoparticles (ZnONPs) and Zinc Oxide nanoparticles doped with Chlorine (Cl:ZnONPs). The chara...In this study we used a chemical solution method from oxalic acid (OX. acid) and zinc acetate (ZnAc) to prepare Zinc Oxide nanoparticles (ZnONPs) and Zinc Oxide nanoparticles doped with Chlorine (Cl:ZnONPs). The characterizations (FTIR, X-ray, SEM, TEM) of ZnONPs and Cl:ZnONPs were determined. Amylase inhibitors of ZnONPs and Cl:ZnONPs also were determined. SEM indicated that the ZnONPs and Cl:ZnONPs have an average particle size of 46.65 - 74.64 nm. TEM images of the ZnONPs and Cl:ZnONPs showed the round shaped. Compounds b,<span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">d and e exhibited significant inhibitory activity against amylase enzyme</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">(from 69.21</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">±</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">1.44 to 76.32</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">±</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.78), respectively, and were comparable with that of acarbose (86.32 ± 0.63) at 1000</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">μg, thereby, projecting ZnONPs and Cl:ZnONPs as </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-amylase inhibitors.</span></span></span></span>展开更多
High transparent and conductive thin films of zinc doped tin oxide （ZTO） were deposited on quartz substrates by the radio-frequency （RF） magnetron sputtering using a 12 wt% ZnO doped with 88 wt% SnO2 ceramic targe...High transparent and conductive thin films of zinc doped tin oxide （ZTO） were deposited on quartz substrates by the radio-frequency （RF） magnetron sputtering using a 12 wt% ZnO doped with 88 wt% SnO2 ceramic target.The effect of substrate temperature on the structural,electrical and optical performances of ZTO films has been studied.X-ray diffraction （XRD） results show that ZTO films possess tetragonal rutile structure with the preferred orientation of （101）.The surface morphology and roughness of the films was investigated by the atomic force microscope （AFM）.The electrical characteristic （including carrier concentration,Hall mobility and resistivity） and optical transmittance were studied by the Hall tester and UV- VIS,respectively.The highest carrier concentration of -1.144×1020 cm-3 and the Hall mobility of 7.018 cm2（V ·sec）-1 for the film with an average transmittance of about 80.0% in the visible region and the lowest resistivity of 1.116×10-2 Ω·cm were obtained when the ZTO films deposited at 250 oC.展开更多
Indium doped zinc oxide （ZnO：In） thin films were prepared by ultrasonic spray pyrolysis on corning eagle 2000 glass substrate. 1 and 2 at.% indium doped single-layer ZnO：In thin films with different amounts of ace...Indium doped zinc oxide （ZnO：In） thin films were prepared by ultrasonic spray pyrolysis on corning eagle 2000 glass substrate. 1 and 2 at.% indium doped single-layer ZnO：In thin films with different amounts of acetic acid added in the initial solution were fabricated. The 1 at.% indium doped single-layers have triangle grains. The 2 at.% indium doped single-layer with 0.18 acetic acid adding has the resistivity of 6.82 × 10^-3 Ω. cm and particle grains. The doublelayers structure is designed to fabricate the ZnO：In thin film with low resistivity （2.58 × 10^-3 Ω. cm） and good surface morphology. It is found that the surface morphology of the double-layer ZnO：In film strongly depends on the substratelayer, and the second-layer plays a large part in the resistivity of the doublewlayer ZnO：In thin film. Both total and direct transmittances of the double-layer ZnO：In film are above 80% in the visible light region. Single junction a-Si：H solar cell based on the double-layer ZnO：In as front electrode is also investigated.展开更多
Cu(copper)-doped ZnO(zinc oxide)was synthesized using Cu(NO3)2·3H2O(copper(II)nitrate)and Zn(NO3)2·6H2O(zinc nitrate)by chemical co-precipitation method.The weight percentages of dopant in solution were Cu(2...Cu(copper)-doped ZnO(zinc oxide)was synthesized using Cu(NO3)2·3H2O(copper(II)nitrate)and Zn(NO3)2·6H2O(zinc nitrate)by chemical co-precipitation method.The weight percentages of dopant in solution were Cu(2,3,and 5 wt%).Cu-doped ZnO thin films were prepared on p-Si(100)substrate by screen printing method.Cu-doped ZnO/Si films were annealed at different temperatures from 300 to 700°C.In this study,Cu-doped ZnO structures were prepared by a simple precipitation technique,and characterized by various techniques such as XRD(X-ray diffraction)and SEM(scanning electron microscope).The electrical properties of Cu-doped ZnO/Si were measured.It has found that Cu-doped ZnO/Si films can be used as optoelectronic devices.展开更多
Cubic （Zn,Li）TiO3 powders were synthesized through a modified sol-gel route including the Pechini process via a three-step heat treatment.The as-synthesized （Zn,Li）TiO3 could be stable up to 1000 °C.The diele...Cubic （Zn,Li）TiO3 powders were synthesized through a modified sol-gel route including the Pechini process via a three-step heat treatment.The as-synthesized （Zn,Li）TiO3 could be stable up to 1000 °C.The dielectric constant and dielectric loss tangent of all the synthesized （Zn,Li）TiO3 samples at different measurement frequencies showed the similar tendency.At the same frequency,the dielectric constant and the dielectric loss tangent of （Zn,Li）TiO3 samples decreased and increased,respectively,with the lithium doping content increase.The as-prepared （Zn,Li）TiO3 showed improved microwave dielectric properties,and its maximum value of quality factor could reach 34000 GHz.展开更多
Prosthetic eye is indispensable as filler after enucleation in patients with anophthalmia,whereas there are still many complications including postoperative infection and eye socket depression or extrusion during the ...Prosthetic eye is indispensable as filler after enucleation in patients with anophthalmia,whereas there are still many complications including postoperative infection and eye socket depression or extrusion during the conventional artificial eye material applications.Some Ca-silicate biomaterials showed superior bioactivity but their biological stability in vivo limit the biomedical application as long-term or permanent implants.Herein we aimed to understand the physicochemical and potential biological responses of zinc doping in wollastonite bioceramic used for orbital implants.The wollastonite powders with different zinc dopant contents(CSi-Znx)could be fabricated as porous implants with strut or curve surface pore geometries(cubic,IWP)via ceramic stereolithography.The experimental results indicated that,by increasing zinc-substituting-Ca ratio(up to 9%),the sintering and mechanical properties could be significantly enhanced,and meanwhile the bio-dissolution in vitro and biodegradability in vivo were thoroughly inhibited.In particular,an appreciable angiogenic activity and expected antibacterial efficacy(over 90%)were synergistically achieved at 9 mol%Zn dopant.In the back-embedding and enucleation and implantation model experiments in rabbits,the superior continuous angiogenesis was corroborated from the 2D/3D fibrovascular reconstruction in the IWP-pore CSi-Zn9 and CSi-Zn13.5 groups within very short time stages.Totally,the present silicate-based bioceramic via selective Zn doping could produce outstanding structural stability and bifunctional biological responses which is especially valuable for developing the next-generation implants with vascular insertion and fixation in orbital reconstruction prothesis.展开更多
Zinc oxide(ZnO) doped with erbium at different concentrations was synthesized by solid-state reaction method and characterized by X-ray diffraction(XRD), scanning electron microscopic(SEM), UVabsorption spectroscopy, ...Zinc oxide(ZnO) doped with erbium at different concentrations was synthesized by solid-state reaction method and characterized by X-ray diffraction(XRD), scanning electron microscopic(SEM), UVabsorption spectroscopy, photoluminescence(PL) study and vibrating sample magnetometer. The XRD studies exhibit the presence of wurtzite crystal structure similar to the parent compound ZnO in 1% Er^(3+)doped Zn O,suggesting that doped Er^(3+)ions sit at the regular Zn^(2+)sites. However, same studies spread over the samples with Er^(3+)content>1% reveals the occurrence of secondary phase. SEM images of 1% Er^(3+)doped ZnO show the polycrystalline nature of the synthesized sample. UV-visible absorption spectrum of Er^(3+)doped ZnO nanocrystals shows a strong absorption peak at 388 nm due to ZnO band to band transition. The PL study exhibits emission in the visible region, due to excitonic as well as defect related transitions. The magnetizationfield curve of Er^(3+)doped ZnO nanocrystals showed ferromagnetic property at room-temperature.展开更多
Mn^2＋ doped Zn2SiO4 phosphors were synthesized by sol-gel method, and the influence of zinc source, Mn^2＋ dopant concentration and annealing temperature were investigated. Results show that zinc nitrate based precur...Mn^2＋ doped Zn2SiO4 phosphors were synthesized by sol-gel method, and the influence of zinc source, Mn^2＋ dopant concentration and annealing temperature were investigated. Results show that zinc nitrate based precursor with strong green emission intensities is better than zinc acetate based precursor. The intensity of green light emission reaches a peak at 254 nm when the Mn^2＋ dopant concentration is about 5%（ molar percentage）. Structural details of the phosphors were examined through X-ray diffractometry, thermogravimetric and differential thermal analysis. The result indicates that they are both rhombohedral structures, which remain amorphous below 700 ℃ and crystallize completely around 1000 ℃. The luminescent properties of Zn2SiO4/Mn^2＋ phosphors were characterized by excitation and emission spectra.展开更多
The synthesis,crystal structure and electrical conductivity properties of Fe-doped ZnO powders（in the range of 0.25-15 mol%） were reported in this paper.I-phase samples,which were indexed as single phase with a hexa...The synthesis,crystal structure and electrical conductivity properties of Fe-doped ZnO powders（in the range of 0.25-15 mol%） were reported in this paper.I-phase samples,which were indexed as single phase with a hexagonal（wurtzite） structure in the Fe-doped ZnO binary system,were determined by X-ray diffraction（XRD）.The solubility limit of Fe in the ZnO lattice is 3 mol% at 950℃.The above mixed phase was observed.And the impurity phase was determined as the cubic-ZnFe 2 O 4 phase when compared with standard XRD data using the PDF program.This study focused on single I-phase ZnO samples which were synthesized at 950℃ because the limit of the solubility range is the widest at this temperature.The lattice parameters a and c of the I-phase decreased with Fe-doping concentration.The morphology of the I-phase samples was analyzed with a scanning electron microscope.The grain size of the I-phase samples increased with heat treatment and doping concentration.The electrical conductivity of the pure ZnO and single I-phase samples was investigated using the four-probe dc method at 100-950℃ in air atmosphere.The electrical conductivity values of pure ZnO,0.25 and 3 mol% Fe-doped ZnO samples at 100℃ were 2×10-6,1.7×10-3 and 6.3×10-4 S.cm-1,and at 950℃ they were 3.4,8.5 and 4 S.cm-1,respectively.展开更多
Zinc hydroxide nitrate, an anionic exchanger layered material, undoped as well as doped with 2-10% nickel, was synthesized by using a pH-controlled precipitation method. The layered materials were then used to produce...Zinc hydroxide nitrate, an anionic exchanger layered material, undoped as well as doped with 2-10% nickel, was synthesized by using a pH-controlled precipitation method. The layered materials were then used to produce the undoped and nickel-doped zinc oxides by hydrothermal-treatment. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the formation of pure phase undoped and nickel-doped layered materials, as well as the products of the hydrothermal- treated materials, nanostructured zinc oxides. Optical studies of the nanostructured zinc oxides showed a decrease in band gap with increasing content of the doping agent, nicke~.展开更多
This paper reported the synthesis, crystal structure and electrical conductivity properties of Ni-doped ZnO powders （i.e. Zn1-xNixO binary system, X=0, 0.0025, 0.005, 0.0075 and in the range 0.01≤X〈0.15）. I- phase...This paper reported the synthesis, crystal structure and electrical conductivity properties of Ni-doped ZnO powders （i.e. Zn1-xNixO binary system, X=0, 0.0025, 0.005, 0.0075 and in the range 0.01≤X〈0.15）. I- phase samples, which were indexed as single phase with a hexagonal （wurtzite） structure in the Zn1-xNixO binary system, were determined by X-ray diffraction （XRD）. The widest range of the I-phase was determined as 0≤X≤0.03 at 1200℃; above this range the mixed phase was observed. The impurity phase was determined as NiO when compared with standard XRD data, using the PDF program. We focused on single f-phase ZnO samples which were synthesized at 1200℃ because of the widest range of solubility limit at this temperature. It was observed that the lattice parameters a and c of the I-phase decreased with Ni doping concentration. The morphology of the I-phase samples was analyzed with a scanning electron microscope. The electrical conductivity of the pure ZnO and single I-phase samples were studied by using the four-probe dc method at temperatures between 100 and 950℃ in air atmosphere. The electrical conductivity values of pure ZnO and 3 mol% Ni-doped ZnO samples at 100℃C were 2×10^-6 and 4.8×10^-6 Ω-1.cm^-1, and at 950℃ they were 1.8 and 3.6 Ω-1cm-1, respectively. In other words, electrical conductivity increased with Ni doping concentration.展开更多
Recently, the localized surface plasmon resonance （LSPR） concept was expanded from noble metals to doped semiconductor nanocrystals （NCs）. However, the strengthening of the intrinsically very weak LSPR in NCs rema...Recently, the localized surface plasmon resonance （LSPR） concept was expanded from noble metals to doped semiconductor nanocrystals （NCs）. However, the strengthening of the intrinsically very weak LSPR in NCs remains a great challenge for its applications in optics, electronics and optoelectronics fields. In this work, we report on the remarkable strengthening and controllability of LSPR in ZnO through a dual-doping strategy. First, high quality In-doped ZnO （IZO） NCs with intense LSPR were synthesized by a simple single-pot method. Importantly, the LSPR can be tuned by simply adjusting the concentration of In dopant, as well as by UV light irradiation （photo-induced doping）. The pattern of electricity of an IZO NC film matches the shift of LSPR independent of dopant concentration. The UV light irradiation clearly enhanced the electrical properties of the films （350 fl/sq） due to increase carrier density explained by LSPR and confirmed by X-ray photoelectron spectroscopy, The IZO NCs can be easily dispersed in various organic solvents and serve as inks for assembling uniform films via solution processes. These IZO NC ink is promising for application in next-generation solution-based field effect transistors and other optoelec- tronic devices.展开更多
The X-ray crystal structure of [(dtma)ZnImZn(dtma)]ClO_4·2.5H_2O (Hdtma=4-Diethyl- enetriamineacetic acid) was determined.The crystal is of orthorhombic,space group Pbcn with a- 14.104(5),b=14.897(5),c=25.384(9),...The X-ray crystal structure of [(dtma)ZnImZn(dtma)]ClO_4·2.5H_2O (Hdtma=4-Diethyl- enetriamineacetic acid) was determined.The crystal is of orthorhombic,space group Pbcn with a- 14.104(5),b=14.897(5),c=25.384(9),and Z=8.The least-square refinement of the structure leads to conventional R factor of 0.066.The magnetic properties of [(dtma)CulmZn(dtma)]CIO_4·2.5H_2O were investigated.From the single crystal ESR spectra of Zn—Im—Zn dimer doped with Cu—Im—Zn complex,the anisotropic g and A tensors and electronic spin-density of the Cu—Zn complex are obtained and the bonding nature of Cu is discussed.展开更多
The electronic structures and optical properties of intrinsic SnO2, Zn-doped SnO2, SnO2 with Sn va- cancy （Vsn） and Zn-doped SnO2 with Sn vacancy are explored by using first-principles calculations. Zn-doped SnO2 is...The electronic structures and optical properties of intrinsic SnO2, Zn-doped SnO2, SnO2 with Sn va- cancy （Vsn） and Zn-doped SnO2 with Sn vacancy are explored by using first-principles calculations. Zn-doped SnO2 is a p-type semiconductor material, whose Fermi level shifts into the valence band when Zn atoms substitute Sn atoms, and the unoccupied states on the top of the valence band come from Zn 3d and O 2p states. Sn vacancies increase the relative hole number of Zn-doped SnO2, which results in a possible increase in the conductivity of Zn-doped SnO2. The Zn-doped SnO2 shows distinct visible light absorption, the increased absorption can be seen apparently with the presence of Sn vacancies in the crystal, and the blue-shift of optical spectra can be observed.展开更多
Single-atom metal-incorporated carbon nanomaterials(CMs)have shown great potential towards broad catalytic applications.In this work,we show that N-doped porous CMs embedded with redox-able Zn atoms exhibit superior c...Single-atom metal-incorporated carbon nanomaterials(CMs)have shown great potential towards broad catalytic applications.In this work,we show that N-doped porous CMs embedded with redox-able Zn atoms exhibit superior capacitive performance.High Zn(~2.72 at.%)/N(~12.51 at.%)doping were realized by incorporating Zn2+and benzamide into the condensation and carbonization of formamide and subsequent annealing at 900℃.The Zn and N species are mutually benefited during the formation of ZnN4 motif.The as-obtained Zn1NC material affords a very large capacitance of 621 F·g^(−1)(at 0.1 A·g^(−1)),superior rate capability(~65%retention at 100 A·g^(−1)),and excellent cycling stability(0.00044%per cycle at 10 A·g^(−1)).These merits are attributed to the high Zn/N loading,atomic Zn-boosted pseudocapacitive behavior,large specific surface area(~1,085 m^(2)·g^(−1)),and rich pore hierarchy,thus ensuring both large pseudo-capacitance(e.g.,~37.9%at 10 mV·s^(−1))and double-layer capacitance.Besides of establishing a new type of high Zn/N-loading carbon materials,our work uncovers the capacitive roles of atomically dispersed metals in CMs.展开更多
Al doped zinc oxide （AZO） films were prepared by mid-frequency magnetron sputtering for silicon （Si） thin film solar cells. Then, the influence of deposition parameters on the electrical and optical properties of ...Al doped zinc oxide （AZO） films were prepared by mid-frequency magnetron sputtering for silicon （Si） thin film solar cells. Then, the influence of deposition parameters on the electrical and optical properties of the films was studied. Results showed that high conductive and high transparent AZO thin films were achieved with a minimum resistivity of 2.45 × 10^-4 Ω·cm and optical transmission greater than 85% in visible spectrum region as the films were deposited at a substrate temperature of 225℃ and a low sputtering power of 160 W. The optimized films were applied as back reflectors in a-SiGe：H solar cells. A relative increase of 19% in the solar cell efficiency was achieved in comparison to the cell without the ZnO films doped with Al （ZnO：Al）.展开更多
基金supported by research grants from the National Research Foundation(NRF-2019H1D3A1A01069779)funded by the Ministry of Science and ICT,Republic of Korea,and by the Institutional Program(2E31863)and Bridge Program-KIST(2V09284).
文摘The practical applications of aqueous Zn metal batteries are currently restricted by the inherent drawbacks of Zn such as the hydrogen evolution reaction,sluggish kinetics,and dendrite formation.To address these problems,herein,a limitedly Zn-doped MgF_(2)interphase comprising an upper region of pure,porous MgF_(2)and a lower region of gradient Zn-doped MgF_(2)is achieved via radio frequency sputtering technique.The porous MgF_(2)region is a polar insulator whose high corrosion resistance facilitates the de-solvation of the solvated Zn ions and suppression of hydrogen evolution,resulting in Zn metal electrodes with a low interfacial resistance.The Zn-doped MgF_(2)region facilitates fast transfer kinetics and homogeneous deposition of Zn ions owing to the interfacial polarization between the Zn dopant and MgF_(2)matrix,and the high concentration of the Zn dopant on the surface of the metal substrate as fine nuclei.Consequently,a symmetric cell incorporating the proposed Zn metal exhibits low overpotentials of~27.2 and~99.7 mV without Zn dendrites over 250 to 8000 cycles at current densities of 1.0 and 10.0 mA cm−2,respectively.The developed Zn/MnO2 full cell exhibits superior capacity retentions of 97.5%and 84.0%with average Coulombic efficiencies of 99.96%after 1000 and 3000 cycles,respectively.
基金supported by the National Natural Science Foundation of China (21633009, 21925206)the National Key R&D Program of China (2020YFA0406102)+2 种基金the Dalian National Laboratory for Clean Energy (DNL) Cooperation Fund,Chinese Academy of Sciences (DNL 201913)the International Partnership Program of Chinese Academy of Sciences (121421KYSB20190025)the DICP foundation of innovative research (DICP I201927)。
文摘Perovskite BaTaO_(2) N(BTON) is one of the most promising photocatalysts for solar water splitting due to its wide visible-light absorption and suitable conduction/valence bands,but it still confronts the challenge of high defect density causing decreased charge separation as well as photocatalytic activity.In this work,we develop a simple zinc doping strategy to greatly suppress its defect density and promote its water reduction performance.It is found that the defect formation on the nitrided Ba(Zn_(1/3-x)Ta_(2/3))O_(3-y)N_z(denoted as BZTON hereafter) will be greatly inhibited when the Zn-doped Ba(Zn_(1/3)Ta_(2/3))O_(3)(BZTO) oxide is used as the nitridation precursor.The structural characterizations and discussion demonstrate that the effective inhibition of Ta^(5+)into Ta^(4+)defects in BZTON mainly results from the easy reduction of zinc ions into metal and further the evaporation of zinc metal under the thermal ammonia flow.Interestingly,this simply doping methodology can be easily extended into the synthesis of SrTaO_(2) N(STON) with extremely low defect density,demonstrating its generality.Benefiting from the successful control to the defect density,the as-obtained BZTON photocatalyst exhibits remarkably promoted charge separation as well as water reduction activity to produce hydrogen with respect to the pristine BTON.Our work may provide an alternative avenue to prepare oxynitride semiconductors with reduced defect density for promoted solar energy conversion.
文摘Aluminum doped zinc oxide （AZO）, as an electrically conductive material, was applied to coating on the surface of olivine-type LiFePO4 synthesized by solid-state method. The charge-discharge test results show that the rate performance and low-temperature performance of LiFePO4 are greatly improved by the surface treatment. Even at 20C rate, the discharge specific capacity of 100.9 mA.h/g was obtained by the AZO-coated LiFePO4 at room temperature. At -20 ℃, the discharge specific capacity at 0.2C for un-coated LiFePO4 and the coated one are 50.3 mA.h/g and 119.4 mA.h/g, respectively. It should be attributed to the electrically conductive AZO-coating which increases the electronic conductivity of LiFePO4. Furthermore, the surface-coating increases the tap-density of LiFePO4. The results indicate that the AZO-coated LiFePO4 is a good candidate of cathode material for applying in lithium power batteries.
文摘In this study we used a chemical solution method from oxalic acid (OX. acid) and zinc acetate (ZnAc) to prepare Zinc Oxide nanoparticles (ZnONPs) and Zinc Oxide nanoparticles doped with Chlorine (Cl:ZnONPs). The characterizations (FTIR, X-ray, SEM, TEM) of ZnONPs and Cl:ZnONPs were determined. Amylase inhibitors of ZnONPs and Cl:ZnONPs also were determined. SEM indicated that the ZnONPs and Cl:ZnONPs have an average particle size of 46.65 - 74.64 nm. TEM images of the ZnONPs and Cl:ZnONPs showed the round shaped. Compounds b,<span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">d and e exhibited significant inhibitory activity against amylase enzyme</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">(from 69.21</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">±</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">1.44 to 76.32</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">±</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">0.78), respectively, and were comparable with that of acarbose (86.32 ± 0.63) at 1000</span></span></span><span><span><span style="font-family:;" "=""> </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">μg, thereby, projecting ZnONPs and Cl:ZnONPs as </span><i><span style="font-family:Verdana;">α</span></i><span style="font-family:Verdana;">-amylase inhibitors.</span></span></span></span>
基金Funded by the Program for Changjiang Scholars and Innovative Research Team in University, Ministry of Education, China (No.IRT0547)
文摘High transparent and conductive thin films of zinc doped tin oxide （ZTO） were deposited on quartz substrates by the radio-frequency （RF） magnetron sputtering using a 12 wt% ZnO doped with 88 wt% SnO2 ceramic target.The effect of substrate temperature on the structural,electrical and optical performances of ZTO films has been studied.X-ray diffraction （XRD） results show that ZTO films possess tetragonal rutile structure with the preferred orientation of （101）.The surface morphology and roughness of the films was investigated by the atomic force microscope （AFM）.The electrical characteristic （including carrier concentration,Hall mobility and resistivity） and optical transmittance were studied by the Hall tester and UV- VIS,respectively.The highest carrier concentration of -1.144×1020 cm-3 and the Hall mobility of 7.018 cm2（V ·sec）-1 for the film with an average transmittance of about 80.0% in the visible region and the lowest resistivity of 1.116×10-2 Ω·cm were obtained when the ZTO films deposited at 250 oC.
基金supported by Hi-Tech Research and Development Program of China (Grant Nos. 2007AA05Z436 and 2009AA050602)Science and Technology Support Project of Tianjin (Grant No. 08ZCKFGX03500)+3 种基金the National Basic Research Program of China (Grant Nos. 2011CB201605 and 2011CB201606)the National Natural Science Foundation of China (Grant No. 60976051)International Cooperation Project between China-Greece Government (Grant No. 2009DFA62580)Program for New Century Excellent Talents in University of China (Grant No. NCET-08-0295)
文摘Indium doped zinc oxide （ZnO：In） thin films were prepared by ultrasonic spray pyrolysis on corning eagle 2000 glass substrate. 1 and 2 at.% indium doped single-layer ZnO：In thin films with different amounts of acetic acid added in the initial solution were fabricated. The 1 at.% indium doped single-layers have triangle grains. The 2 at.% indium doped single-layer with 0.18 acetic acid adding has the resistivity of 6.82 × 10^-3 Ω. cm and particle grains. The doublelayers structure is designed to fabricate the ZnO：In thin film with low resistivity （2.58 × 10^-3 Ω. cm） and good surface morphology. It is found that the surface morphology of the double-layer ZnO：In film strongly depends on the substratelayer, and the second-layer plays a large part in the resistivity of the doublewlayer ZnO：In thin film. Both total and direct transmittances of the double-layer ZnO：In film are above 80% in the visible light region. Single junction a-Si：H solar cell based on the double-layer ZnO：In as front electrode is also investigated.
文摘Cu(copper)-doped ZnO(zinc oxide)was synthesized using Cu(NO3)2·3H2O(copper(II)nitrate)and Zn(NO3)2·6H2O(zinc nitrate)by chemical co-precipitation method.The weight percentages of dopant in solution were Cu(2,3,and 5 wt%).Cu-doped ZnO thin films were prepared on p-Si(100)substrate by screen printing method.Cu-doped ZnO/Si films were annealed at different temperatures from 300 to 700°C.In this study,Cu-doped ZnO structures were prepared by a simple precipitation technique,and characterized by various techniques such as XRD(X-ray diffraction)and SEM(scanning electron microscope).The electrical properties of Cu-doped ZnO/Si were measured.It has found that Cu-doped ZnO/Si films can be used as optoelectronic devices.
基金Supported by the National Natural Science Foundation of China(Nos.20731001,20871015 and 50725415)the Program for New Century Excellent Talents in University,China(NCET)+1 种基金the National Basic Research Program of China(No.2007CB613601)the Program for Changjiang Scholars and Innovative Research Team in University,China(No.IRT0708)
文摘Cubic （Zn,Li）TiO3 powders were synthesized through a modified sol-gel route including the Pechini process via a three-step heat treatment.The as-synthesized （Zn,Li）TiO3 could be stable up to 1000 °C.The dielectric constant and dielectric loss tangent of all the synthesized （Zn,Li）TiO3 samples at different measurement frequencies showed the similar tendency.At the same frequency,the dielectric constant and the dielectric loss tangent of （Zn,Li）TiO3 samples decreased and increased,respectively,with the lithium doping content increase.The as-prepared （Zn,Li）TiO3 showed improved microwave dielectric properties,and its maximum value of quality factor could reach 34000 GHz.
基金the National Natural Science Foundation Regional Innovation and Development Joint Fund(U20A20386)the Zhejiang Provincial Basic Research for Public Welfare Funds(LGF22E030002)+1 种基金National Natural Science Foundation of China(82330032,82201236)Zhejiang Provincial Natural Science Foundation of China(LZ22E020002).
文摘Prosthetic eye is indispensable as filler after enucleation in patients with anophthalmia,whereas there are still many complications including postoperative infection and eye socket depression or extrusion during the conventional artificial eye material applications.Some Ca-silicate biomaterials showed superior bioactivity but their biological stability in vivo limit the biomedical application as long-term or permanent implants.Herein we aimed to understand the physicochemical and potential biological responses of zinc doping in wollastonite bioceramic used for orbital implants.The wollastonite powders with different zinc dopant contents(CSi-Znx)could be fabricated as porous implants with strut or curve surface pore geometries(cubic,IWP)via ceramic stereolithography.The experimental results indicated that,by increasing zinc-substituting-Ca ratio(up to 9%),the sintering and mechanical properties could be significantly enhanced,and meanwhile the bio-dissolution in vitro and biodegradability in vivo were thoroughly inhibited.In particular,an appreciable angiogenic activity and expected antibacterial efficacy(over 90%)were synergistically achieved at 9 mol%Zn dopant.In the back-embedding and enucleation and implantation model experiments in rabbits,the superior continuous angiogenesis was corroborated from the 2D/3D fibrovascular reconstruction in the IWP-pore CSi-Zn9 and CSi-Zn13.5 groups within very short time stages.Totally,the present silicate-based bioceramic via selective Zn doping could produce outstanding structural stability and bifunctional biological responses which is especially valuable for developing the next-generation implants with vascular insertion and fixation in orbital reconstruction prothesis.
文摘Zinc oxide(ZnO) doped with erbium at different concentrations was synthesized by solid-state reaction method and characterized by X-ray diffraction(XRD), scanning electron microscopic(SEM), UVabsorption spectroscopy, photoluminescence(PL) study and vibrating sample magnetometer. The XRD studies exhibit the presence of wurtzite crystal structure similar to the parent compound ZnO in 1% Er^(3+)doped Zn O,suggesting that doped Er^(3+)ions sit at the regular Zn^(2+)sites. However, same studies spread over the samples with Er^(3+)content>1% reveals the occurrence of secondary phase. SEM images of 1% Er^(3+)doped ZnO show the polycrystalline nature of the synthesized sample. UV-visible absorption spectrum of Er^(3+)doped ZnO nanocrystals shows a strong absorption peak at 388 nm due to ZnO band to band transition. The PL study exhibits emission in the visible region, due to excitonic as well as defect related transitions. The magnetizationfield curve of Er^(3+)doped ZnO nanocrystals showed ferromagnetic property at room-temperature.
文摘Mn^2＋ doped Zn2SiO4 phosphors were synthesized by sol-gel method, and the influence of zinc source, Mn^2＋ dopant concentration and annealing temperature were investigated. Results show that zinc nitrate based precursor with strong green emission intensities is better than zinc acetate based precursor. The intensity of green light emission reaches a peak at 254 nm when the Mn^2＋ dopant concentration is about 5%（ molar percentage）. Structural details of the phosphors were examined through X-ray diffractometry, thermogravimetric and differential thermal analysis. The result indicates that they are both rhombohedral structures, which remain amorphous below 700 ℃ and crystallize completely around 1000 ℃. The luminescent properties of Zn2SiO4/Mn^2＋ phosphors were characterized by excitation and emission spectra.
基金supported by the Research Foundation of Erciyes University (Kayseri,Turkey)
文摘The synthesis,crystal structure and electrical conductivity properties of Fe-doped ZnO powders（in the range of 0.25-15 mol%） were reported in this paper.I-phase samples,which were indexed as single phase with a hexagonal（wurtzite） structure in the Fe-doped ZnO binary system,were determined by X-ray diffraction（XRD）.The solubility limit of Fe in the ZnO lattice is 3 mol% at 950℃.The above mixed phase was observed.And the impurity phase was determined as the cubic-ZnFe 2 O 4 phase when compared with standard XRD data using the PDF program.This study focused on single I-phase ZnO samples which were synthesized at 950℃ because the limit of the solubility range is the widest at this temperature.The lattice parameters a and c of the I-phase decreased with Fe-doping concentration.The morphology of the I-phase samples was analyzed with a scanning electron microscope.The grain size of the I-phase samples increased with heat treatment and doping concentration.The electrical conductivity of the pure ZnO and single I-phase samples was investigated using the four-probe dc method at 100-950℃ in air atmosphere.The electrical conductivity values of pure ZnO,0.25 and 3 mol% Fe-doped ZnO samples at 100℃ were 2×10-6,1.7×10-3 and 6.3×10-4 S.cm-1,and at 950℃ they were 3.4,8.5 and 4 S.cm-1,respectively.
文摘Zinc hydroxide nitrate, an anionic exchanger layered material, undoped as well as doped with 2-10% nickel, was synthesized by using a pH-controlled precipitation method. The layered materials were then used to produce the undoped and nickel-doped zinc oxides by hydrothermal-treatment. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the formation of pure phase undoped and nickel-doped layered materials, as well as the products of the hydrothermal- treated materials, nanostructured zinc oxides. Optical studies of the nanostructured zinc oxides showed a decrease in band gap with increasing content of the doping agent, nicke~.
基金supported by the Research Foundation of Erciyes University (Kayseri,Turkey)
文摘This paper reported the synthesis, crystal structure and electrical conductivity properties of Ni-doped ZnO powders （i.e. Zn1-xNixO binary system, X=0, 0.0025, 0.005, 0.0075 and in the range 0.01≤X〈0.15）. I- phase samples, which were indexed as single phase with a hexagonal （wurtzite） structure in the Zn1-xNixO binary system, were determined by X-ray diffraction （XRD）. The widest range of the I-phase was determined as 0≤X≤0.03 at 1200℃; above this range the mixed phase was observed. The impurity phase was determined as NiO when compared with standard XRD data, using the PDF program. We focused on single f-phase ZnO samples which were synthesized at 1200℃ because of the widest range of solubility limit at this temperature. It was observed that the lattice parameters a and c of the I-phase decreased with Ni doping concentration. The morphology of the I-phase samples was analyzed with a scanning electron microscope. The electrical conductivity of the pure ZnO and single I-phase samples were studied by using the four-probe dc method at temperatures between 100 and 950℃ in air atmosphere. The electrical conductivity values of pure ZnO and 3 mol% Ni-doped ZnO samples at 100℃C were 2×10^-6 and 4.8×10^-6 Ω-1.cm^-1, and at 950℃ they were 1.8 and 3.6 Ω-1cm-1, respectively. In other words, electrical conductivity increased with Ni doping concentration.
基金supported by the National Key Research and Development Program of China (2016YFB0401701)the National Basic Research Program of China (2014CB931702)+5 种基金the National Natural Science Foundation of China (61604074, 51572128)the National Natural Science Foundation of China and the Research Grants Council (NSFC-RGC5151101197)the Natural Science Foundation of Jiangsu Province (BK20160827)the China Postdoctoral Science Foundation (2016M590455)the Fundamental Research Funds for the Central Universities (30915012205, 30916015106)PAPD of Jiangsu Higher Education Institutions, the Opened Fund of the State Key Laboratory on Integrated Optoelectronics (2015IOSKLKF15)
文摘Recently, the localized surface plasmon resonance （LSPR） concept was expanded from noble metals to doped semiconductor nanocrystals （NCs）. However, the strengthening of the intrinsically very weak LSPR in NCs remains a great challenge for its applications in optics, electronics and optoelectronics fields. In this work, we report on the remarkable strengthening and controllability of LSPR in ZnO through a dual-doping strategy. First, high quality In-doped ZnO （IZO） NCs with intense LSPR were synthesized by a simple single-pot method. Importantly, the LSPR can be tuned by simply adjusting the concentration of In dopant, as well as by UV light irradiation （photo-induced doping）. The pattern of electricity of an IZO NC film matches the shift of LSPR independent of dopant concentration. The UV light irradiation clearly enhanced the electrical properties of the films （350 fl/sq） due to increase carrier density explained by LSPR and confirmed by X-ray photoelectron spectroscopy, The IZO NCs can be easily dispersed in various organic solvents and serve as inks for assembling uniform films via solution processes. These IZO NC ink is promising for application in next-generation solution-based field effect transistors and other optoelec- tronic devices.
文摘The X-ray crystal structure of [(dtma)ZnImZn(dtma)]ClO_4·2.5H_2O (Hdtma=4-Diethyl- enetriamineacetic acid) was determined.The crystal is of orthorhombic,space group Pbcn with a- 14.104(5),b=14.897(5),c=25.384(9),and Z=8.The least-square refinement of the structure leads to conventional R factor of 0.066.The magnetic properties of [(dtma)CulmZn(dtma)]CIO_4·2.5H_2O were investigated.From the single crystal ESR spectra of Zn—Im—Zn dimer doped with Cu—Im—Zn complex,the anisotropic g and A tensors and electronic spin-density of the Cu—Zn complex are obtained and the bonding nature of Cu is discussed.
基金supported by the National Natural Science Foundation of China(No.10974077)the Innovation Project of Shandong Graduate Education,China(No.SDYY13093)
文摘The electronic structures and optical properties of intrinsic SnO2, Zn-doped SnO2, SnO2 with Sn va- cancy （Vsn） and Zn-doped SnO2 with Sn vacancy are explored by using first-principles calculations. Zn-doped SnO2 is a p-type semiconductor material, whose Fermi level shifts into the valence band when Zn atoms substitute Sn atoms, and the unoccupied states on the top of the valence band come from Zn 3d and O 2p states. Sn vacancies increase the relative hole number of Zn-doped SnO2, which results in a possible increase in the conductivity of Zn-doped SnO2. The Zn-doped SnO2 shows distinct visible light absorption, the increased absorption can be seen apparently with the presence of Sn vacancies in the crystal, and the blue-shift of optical spectra can be observed.
基金the National Natural Science Foundation of China(Nos.22071137 and 21701101)the Shandong Scientific Research Awards Foundation for Outstanding Young Scientists(No.ZR2018JL010)+1 种基金the Natural Science Foundation of Shandong Province(No.ZR2020MB045)the Program for Tsingtao Al-ion Power and Energy-storage Battery Research Team in the University(No.17-2-1-1-zhc).
文摘Single-atom metal-incorporated carbon nanomaterials(CMs)have shown great potential towards broad catalytic applications.In this work,we show that N-doped porous CMs embedded with redox-able Zn atoms exhibit superior capacitive performance.High Zn(~2.72 at.%)/N(~12.51 at.%)doping were realized by incorporating Zn2+and benzamide into the condensation and carbonization of formamide and subsequent annealing at 900℃.The Zn and N species are mutually benefited during the formation of ZnN4 motif.The as-obtained Zn1NC material affords a very large capacitance of 621 F·g^(−1)(at 0.1 A·g^(−1)),superior rate capability(~65%retention at 100 A·g^(−1)),and excellent cycling stability(0.00044%per cycle at 10 A·g^(−1)).These merits are attributed to the high Zn/N loading,atomic Zn-boosted pseudocapacitive behavior,large specific surface area(~1,085 m^(2)·g^(−1)),and rich pore hierarchy,thus ensuring both large pseudo-capacitance(e.g.,~37.9%at 10 mV·s^(−1))and double-layer capacitance.Besides of establishing a new type of high Zn/N-loading carbon materials,our work uncovers the capacitive roles of atomically dispersed metals in CMs.
基金Acknowledgements This work was supported by Key Project of Natural Science Foundation of Hubei Province （No. 2009CBA025）. The authors would like to thank Analytical and Testing Center of Huazhong University of Science and Technology.
文摘Al doped zinc oxide （AZO） films were prepared by mid-frequency magnetron sputtering for silicon （Si） thin film solar cells. Then, the influence of deposition parameters on the electrical and optical properties of the films was studied. Results showed that high conductive and high transparent AZO thin films were achieved with a minimum resistivity of 2.45 × 10^-4 Ω·cm and optical transmission greater than 85% in visible spectrum region as the films were deposited at a substrate temperature of 225℃ and a low sputtering power of 160 W. The optimized films were applied as back reflectors in a-SiGe：H solar cells. A relative increase of 19% in the solar cell efficiency was achieved in comparison to the cell without the ZnO films doped with Al （ZnO：Al）.
