Oxygen anion redox chemistry in layered oxide cathodes for sodium-ion batteries has attracted great interest.However,the release of lattice oxygen caused by the irreversible anionic redox and Jahn–Teller effect accel...Oxygen anion redox chemistry in layered oxide cathodes for sodium-ion batteries has attracted great interest.However,the release of lattice oxygen caused by the irreversible anionic redox and Jahn–Teller effect accelerates the structural distortion and electrochemical degradation.Herein,we rationally construct a stable crystal lattice to enhance the reactivity and reversibility of oxygen redox and inhibit the Jahn–Teller effect by Sn doping.The stronger binding energy of Sn–O enhances the structural stability of the cathode,which is favorable to suppress the oxygen release and Jahn–Teller effect.Thus,the reversibility of oxygen redox and the stability of the layered structure are enhanced.The expansion of the interlayer spacing decreases the energy barriers for Na+ion intercalation,improving the rate performance of the electrode.Benefitting from the rational design,the electrode delivers an enhanced rate performance and cycling stability.This work offers some insights into tuning the oxygen anion redox chemistry as well as suppressing the Jahn–Teller effect by lattice modulation.展开更多
The development of efficient and robust anode materials for stable alkaline seawater electrolysis is severely limited by chlorine evolution reaction and chloride corrosion.Here,the sulfur-doped cobalt-nickel bimetalli...The development of efficient and robust anode materials for stable alkaline seawater electrolysis is severely limited by chlorine evolution reaction and chloride corrosion.Here,the sulfur-doped cobalt-nickel bimetallic phosphides(CoNiPS)are specifically designed as a pre-catalyst for navigating a surface reconstruction to fabricate the anions(PO^(3-)_(4) and SO^(2-)_(4))-decorated Co(Ni)OOH catalyst(R-CoNiPS)with exceptional durability and high activity for stable alkaline seawater oxidation(ASO).Various experiment techniques together with theoretical simulations both demonstrate that the in situ-generated PO^(3-)_(4) and SO^(2-)_(4) anions on catalyst surface can improve the oxygen evolution reaction(OER)activity,regulating and stabilizing the catalytic active species Co(Ni)OOH,as well as make a critical role in inhibiting the adsorp-tion of chloride ions and extending the service life of electrode.Therefore,this R-CoNiPS electrode exhi-bits superb OER activity toward AsO and stands out among the non-precious ASO electrocatalysts reported recently,requiring low overpotentials of 420 and 440 mV to attain large current densities of 500 and 1000 mA cm^(-2) in an alkaline natural seawater electrolyte,respectively.Particularly,the catalyst displays a negligible chloride corrosion at room temperature during ASO operation(>200 h)at 500 mA cm^(-2).This work opens up a new viewpoint for designing high-activity and durable electrocata-lystsforseawaterelectrolysis.展开更多
This paper, for the first time, reports a method that can be used as a highly sensitive probe for singlet oxygen (1O2) and superoxide anion (O2-) in vitro or in vivo. FCLA(3,7-dihydro-6-{4-[2-(N'-(5-fluoresceinyl)...This paper, for the first time, reports a method that can be used as a highly sensitive probe for singlet oxygen (1O2) and superoxide anion (O2-) in vitro or in vivo. FCLA(3,7-dihydro-6-{4-[2-(N'-(5-fluoresceinyl)thioureido)ethoxy]phenyl}-2-methylimidazo{1,2-a}pyrazin-3-one sodium salt), a chemiluminescence (CL) analysis reagent, has been reported to sensitively react with 1O2 and O2- to emit photons with a spectral peak of 525nm. In this work, when human serum albumin (HSA) was added into FCLA solution to enhance the CL intensity, approximately 20 times, compared to that without HSA. The enhanced CL had the same 525 nm spectral peak, identical to that without HSA. By gradually reducing the molecular oxygen content in the solution, we find that the auto-oxidation of oxygen molecules dissolved in the solution plays an important role in the CL process. Based on these experimental evidences, we propose a novel and highly sensitive detection method of 1O2 and O2-, which may have a great potential in chemical and medical applications.展开更多
UAtomic oxygen radical anion (O-) is one of the most active oxygen species, and has extremely high oxidation ability toward small-molecules of hydrocarbons. However, to our knowledge, little is known about the effec...UAtomic oxygen radical anion (O-) is one of the most active oxygen species, and has extremely high oxidation ability toward small-molecules of hydrocarbons. However, to our knowledge, little is known about the effects of O- on cells of micro-organisms. This work showed that O- could quickly react with the Bacillus subtilis cells and seriously damage the cell walls a s well as their other contents, leading to a fast and irreversible inactivation. SEM micrographs revealed that the cell structures were dramatically destroyed by their exposure to O-. The inactivation efficiencies of B. subtilis depend on the O- intensity, the initial population of cells and the treatment temperature, but not on the pH in the range of our investigation. For a cell concentration of 10^6 cfu/ml, the number of survived cells dropped from 10^6 cfu/ml to 10^3 cfu/ml after about five-minute irradiation by an O- flux in an intensity of 233 nA/cm^2 under a dry argon environment (30 ℃, 1 atm, exposed size: 1.8 cm^2). The inactivation mechanism of micro-organisms induced by O- is also discussed.展开更多
We deposited indium-tin-oxide(ITO)films on silicon and quartz substrates by magnetron sputtering technology in pure argon.Using electrostatic quadrupole plasma diagnostic technology,we investigate the effects of disch...We deposited indium-tin-oxide(ITO)films on silicon and quartz substrates by magnetron sputtering technology in pure argon.Using electrostatic quadrupole plasma diagnostic technology,we investigate the effects of discharge power and discharge pressure on the ion flux and energy distribution function of incidence on the substrate surface,with special attention to the production of high-energy negative oxygen ions,and elucidate the mechanism behind its production.At the same time,the structure and properties of ITO films are systematically characterized to understand the potential effects of high energy oxygen ions on the growth of ITO films.Combining with the kinetic property analysis of sputtering damage mechanism of transparent conductive oxide(TCO)thin films,this study provides valuable physical understanding of optimization of TCO thin film deposition process.展开更多
Reactive oxygen species (ROS) can be produced by interactions between sunlight and light-absorbing substances in natural water environment. ROS may participate in the indirect photolysis of trace organic pollutants,...Reactive oxygen species (ROS) can be produced by interactions between sunlight and light-absorbing substances in natural water environment. ROS may participate in the indirect photolysis of trace organic pollutants, therefore resulting in changes in their environmental fates and ecological risks in natural water systems. Bisphenol A (BPA), an endocrine-disrupting chemical, exits widely in natural waters. The photodegradation of BPA promoted by ROS (-OH, 1O2, HO2./O2^-), which were produced on the excitation of ubiquitous constituents (such as nitrate ion, humic substances and Fe(Ⅲ)-oxalate complexes) in natural water under simulated solar radiation was investigated. Both molecular probe method and electron spin resonance (ESR) test were used for the characterization of the generated ROS. It was found that .OH was photochemically produced in the presence of nitrate ions, humic substances and Fe(Ⅲ)-oxalate complexes and that 102 was produced with the presence of humic substances. The steady-state concentrations of .OH was 1.27×10^-14 mol/L in a nitrate solution, and the second-order rate constant of BPA with "OH was 1.01×10^10 L/(mol.s).展开更多
To satisfy the rapid development of gas-involving electrocatalysis(O2, CO2, N2, etc.), nanostructured electrocatalysts with favorably regulated electronic structure and surface nanostructures are urgently required. He...To satisfy the rapid development of gas-involving electrocatalysis(O2, CO2, N2, etc.), nanostructured electrocatalysts with favorably regulated electronic structure and surface nanostructures are urgently required. Herein, we highlighted a core-branch hydroxysulfide as a significantly enhanced oxygen evolution reaction electrocatalyst. This hydroxysulfide was facilely fabricated via a versatile interfacial reaction in S2- inorganic solution at room temperature for a designed period. The moderative growth kinetics contributed to the growth of interconnected hydroxysulfide nanosheets with high-sulfur contents on the hydroxide precursor substrates, resulting in a hierarchical nanostructure with multifunctional modifications, including regulated electronic structure, rapid electron highway, excellent accessibility, and facilitated mass transfer. Such synthetic methodology can be generalized and facilely governed by regulating the temperature, concentration, duration, and solvent for targeted nanostructures. Contributed to the favorably regulated electronic structure and surface nanostructure, the as-obtained core-branch Co2NiS2.4(OH)1.2 sample exhibits superior OER performance, with a remarkably low overpotential(279 m V required for 10.0 m A c^m-2), a low Tafel slope(52 m V dec^-1), and a favorable long-term stability. This work not only presents a promising nanostructured hydroxysulfide for excellent OER electrocatalysis, but also shed fresh lights on the further rational development of efficient electrocatalysts.展开更多
Designing and/or searching for novel antioxidants against oxygen glucose effective strategy for the treatment of human isdlemic stroke. Selenium is deprivation (OGD)-induced oxidative damage represents an an essenti...Designing and/or searching for novel antioxidants against oxygen glucose effective strategy for the treatment of human isdlemic stroke. Selenium is deprivation (OGD)-induced oxidative damage represents an an essential trace dement, which is beneficial in the chemo- prevention and chemotherapy of cerebral ischemic stroke. The underlying mechanisms for its therapeutic effects, however, are not well documented. Selenocysteine (SeC) is a selenium-containing amino acid with neuroprotective potential. Studies have shown that SeC can reduce irradiation-induced DNA apoptosis by reducing DNA damage. In this study, the in vitro protective potential and mechanism of action of SeC against OGD-induced apoptosis and neurotoxicity were evaluated in HT22 mouse hippocampal neurons. We cultured HT22 cells in a glucose-free medium containing 2 mM Na2S402, which formed an OGD environment, for 90 minutes. Findings from MTT, flow cytometry and TUNEL staining showed obvious cytotoxicity and apoptosis in HT22 cells in the OGD condition. The activation of Caspa se-7 and Caspase-9 further revealed that OGD-induced apoptosis of HT22 cells was mainly achieved by triggering a mitochondrial-medi- ated pathway. Moreover, the OGD condition also induced serious DNA damage through the accumulation of reactive oxygen species and superoxide anions. However, SeC pre-treatment for 6 hours effectively inhibited OGD-induced cytotoxicity and apoptosis in HT22 cells by inhibiting reactive oxygen species-mediated oxidative damage. Our findings provide evidence that SeC has the potential to suppress OGD-induced oxidative damage and apoptosis in hippocampal neurons.展开更多
基金the National Natural Science Foundation of China(grant nos.11975238 and 11575192)the Chinese Academy of Sciences(grant nos.ZDKYYQ20170001,211211KYSB20170060,and 211211KYSB20180020)the Natural Science Foundation of Beijing Municipality(grant no.2182082).
文摘Oxygen anion redox chemistry in layered oxide cathodes for sodium-ion batteries has attracted great interest.However,the release of lattice oxygen caused by the irreversible anionic redox and Jahn–Teller effect accelerates the structural distortion and electrochemical degradation.Herein,we rationally construct a stable crystal lattice to enhance the reactivity and reversibility of oxygen redox and inhibit the Jahn–Teller effect by Sn doping.The stronger binding energy of Sn–O enhances the structural stability of the cathode,which is favorable to suppress the oxygen release and Jahn–Teller effect.Thus,the reversibility of oxygen redox and the stability of the layered structure are enhanced.The expansion of the interlayer spacing decreases the energy barriers for Na+ion intercalation,improving the rate performance of the electrode.Benefitting from the rational design,the electrode delivers an enhanced rate performance and cycling stability.This work offers some insights into tuning the oxygen anion redox chemistry as well as suppressing the Jahn–Teller effect by lattice modulation.
基金the funding support from the National Natural Science Foundation of China (U22A2078)the Fundamental Research Funds of Central Universities (2022CDJQY-007 and 2022CDJJCLK001)
文摘The development of efficient and robust anode materials for stable alkaline seawater electrolysis is severely limited by chlorine evolution reaction and chloride corrosion.Here,the sulfur-doped cobalt-nickel bimetallic phosphides(CoNiPS)are specifically designed as a pre-catalyst for navigating a surface reconstruction to fabricate the anions(PO^(3-)_(4) and SO^(2-)_(4))-decorated Co(Ni)OOH catalyst(R-CoNiPS)with exceptional durability and high activity for stable alkaline seawater oxidation(ASO).Various experiment techniques together with theoretical simulations both demonstrate that the in situ-generated PO^(3-)_(4) and SO^(2-)_(4) anions on catalyst surface can improve the oxygen evolution reaction(OER)activity,regulating and stabilizing the catalytic active species Co(Ni)OOH,as well as make a critical role in inhibiting the adsorp-tion of chloride ions and extending the service life of electrode.Therefore,this R-CoNiPS electrode exhi-bits superb OER activity toward AsO and stands out among the non-precious ASO electrocatalysts reported recently,requiring low overpotentials of 420 and 440 mV to attain large current densities of 500 and 1000 mA cm^(-2) in an alkaline natural seawater electrolyte,respectively.Particularly,the catalyst displays a negligible chloride corrosion at room temperature during ASO operation(>200 h)at 500 mA cm^(-2).This work opens up a new viewpoint for designing high-activity and durable electrocata-lystsforseawaterelectrolysis.
文摘This paper, for the first time, reports a method that can be used as a highly sensitive probe for singlet oxygen (1O2) and superoxide anion (O2-) in vitro or in vivo. FCLA(3,7-dihydro-6-{4-[2-(N'-(5-fluoresceinyl)thioureido)ethoxy]phenyl}-2-methylimidazo{1,2-a}pyrazin-3-one sodium salt), a chemiluminescence (CL) analysis reagent, has been reported to sensitively react with 1O2 and O2- to emit photons with a spectral peak of 525nm. In this work, when human serum albumin (HSA) was added into FCLA solution to enhance the CL intensity, approximately 20 times, compared to that without HSA. The enhanced CL had the same 525 nm spectral peak, identical to that without HSA. By gradually reducing the molecular oxygen content in the solution, we find that the auto-oxidation of oxygen molecules dissolved in the solution plays an important role in the CL process. Based on these experimental evidences, we propose a novel and highly sensitive detection method of 1O2 and O2-, which may have a great potential in chemical and medical applications.
基金the innovation program 2002 by CAS in China,(No.KJ0364)
文摘UAtomic oxygen radical anion (O-) is one of the most active oxygen species, and has extremely high oxidation ability toward small-molecules of hydrocarbons. However, to our knowledge, little is known about the effects of O- on cells of micro-organisms. This work showed that O- could quickly react with the Bacillus subtilis cells and seriously damage the cell walls a s well as their other contents, leading to a fast and irreversible inactivation. SEM micrographs revealed that the cell structures were dramatically destroyed by their exposure to O-. The inactivation efficiencies of B. subtilis depend on the O- intensity, the initial population of cells and the treatment temperature, but not on the pH in the range of our investigation. For a cell concentration of 10^6 cfu/ml, the number of survived cells dropped from 10^6 cfu/ml to 10^3 cfu/ml after about five-minute irradiation by an O- flux in an intensity of 233 nA/cm^2 under a dry argon environment (30 ℃, 1 atm, exposed size: 1.8 cm^2). The inactivation mechanism of micro-organisms induced by O- is also discussed.
基金supported by the National Key R&D Program of China(Grant No.2022YFE03050001)the National Natural Science Foundation of China(Grant Nos.12175160 and 12305284).The authors thank Suzhou Maxwell Technologies Co.,Ltd.for partial hardware and particle financial support to carry out the research.
文摘We deposited indium-tin-oxide(ITO)films on silicon and quartz substrates by magnetron sputtering technology in pure argon.Using electrostatic quadrupole plasma diagnostic technology,we investigate the effects of discharge power and discharge pressure on the ion flux and energy distribution function of incidence on the substrate surface,with special attention to the production of high-energy negative oxygen ions,and elucidate the mechanism behind its production.At the same time,the structure and properties of ITO films are systematically characterized to understand the potential effects of high energy oxygen ions on the growth of ITO films.Combining with the kinetic property analysis of sputtering damage mechanism of transparent conductive oxide(TCO)thin films,this study provides valuable physical understanding of optimization of TCO thin film deposition process.
文摘Reactive oxygen species (ROS) can be produced by interactions between sunlight and light-absorbing substances in natural water environment. ROS may participate in the indirect photolysis of trace organic pollutants, therefore resulting in changes in their environmental fates and ecological risks in natural water systems. Bisphenol A (BPA), an endocrine-disrupting chemical, exits widely in natural waters. The photodegradation of BPA promoted by ROS (-OH, 1O2, HO2./O2^-), which were produced on the excitation of ubiquitous constituents (such as nitrate ion, humic substances and Fe(Ⅲ)-oxalate complexes) in natural water under simulated solar radiation was investigated. Both molecular probe method and electron spin resonance (ESR) test were used for the characterization of the generated ROS. It was found that .OH was photochemically produced in the presence of nitrate ions, humic substances and Fe(Ⅲ)-oxalate complexes and that 102 was produced with the presence of humic substances. The steady-state concentrations of .OH was 1.27×10^-14 mol/L in a nitrate solution, and the second-order rate constant of BPA with "OH was 1.01×10^10 L/(mol.s).
基金supported by the National Key Research and Development Program(2016YFA0202500 and 2016YFA0200101)the Natural Scientific Foundation of China(21825501)
文摘To satisfy the rapid development of gas-involving electrocatalysis(O2, CO2, N2, etc.), nanostructured electrocatalysts with favorably regulated electronic structure and surface nanostructures are urgently required. Herein, we highlighted a core-branch hydroxysulfide as a significantly enhanced oxygen evolution reaction electrocatalyst. This hydroxysulfide was facilely fabricated via a versatile interfacial reaction in S2- inorganic solution at room temperature for a designed period. The moderative growth kinetics contributed to the growth of interconnected hydroxysulfide nanosheets with high-sulfur contents on the hydroxide precursor substrates, resulting in a hierarchical nanostructure with multifunctional modifications, including regulated electronic structure, rapid electron highway, excellent accessibility, and facilitated mass transfer. Such synthetic methodology can be generalized and facilely governed by regulating the temperature, concentration, duration, and solvent for targeted nanostructures. Contributed to the favorably regulated electronic structure and surface nanostructure, the as-obtained core-branch Co2NiS2.4(OH)1.2 sample exhibits superior OER performance, with a remarkably low overpotential(279 m V required for 10.0 m A c^m-2), a low Tafel slope(52 m V dec^-1), and a favorable long-term stability. This work not only presents a promising nanostructured hydroxysulfide for excellent OER electrocatalysis, but also shed fresh lights on the further rational development of efficient electrocatalysts.
基金supported by the Sci-Tech Development Project of Taian in Shandong,No.2016NS1058&2015NS2081the Sci-Tech Development Project of Linyi in Shandong,No.201515006
文摘Designing and/or searching for novel antioxidants against oxygen glucose effective strategy for the treatment of human isdlemic stroke. Selenium is deprivation (OGD)-induced oxidative damage represents an an essential trace dement, which is beneficial in the chemo- prevention and chemotherapy of cerebral ischemic stroke. The underlying mechanisms for its therapeutic effects, however, are not well documented. Selenocysteine (SeC) is a selenium-containing amino acid with neuroprotective potential. Studies have shown that SeC can reduce irradiation-induced DNA apoptosis by reducing DNA damage. In this study, the in vitro protective potential and mechanism of action of SeC against OGD-induced apoptosis and neurotoxicity were evaluated in HT22 mouse hippocampal neurons. We cultured HT22 cells in a glucose-free medium containing 2 mM Na2S402, which formed an OGD environment, for 90 minutes. Findings from MTT, flow cytometry and TUNEL staining showed obvious cytotoxicity and apoptosis in HT22 cells in the OGD condition. The activation of Caspa se-7 and Caspase-9 further revealed that OGD-induced apoptosis of HT22 cells was mainly achieved by triggering a mitochondrial-medi- ated pathway. Moreover, the OGD condition also induced serious DNA damage through the accumulation of reactive oxygen species and superoxide anions. However, SeC pre-treatment for 6 hours effectively inhibited OGD-induced cytotoxicity and apoptosis in HT22 cells by inhibiting reactive oxygen species-mediated oxidative damage. Our findings provide evidence that SeC has the potential to suppress OGD-induced oxidative damage and apoptosis in hippocampal neurons.