The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first ti...The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091.展开更多
A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii (BZ) oscillating chemical system. Introducing o...A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii (BZ) oscillating chemical system. Introducing of S^2- ion makes the new oscillating system Ce(SO4)2 - KBrO3 - CH2(COOH)2 - Na2S - H2SO4 have to a high sensitivity for some heavy metal ions such as Ag^+, Pb^2+, Hg^2+, Cd^2+, Cu^2+and Bi^3+ with detection limits down to 10^-12 mol·L^- 1展开更多
Impeding high temperature sintering is challengeable for synthesis of carbon-supported single-atom catalysts (C-SACs), which requires high-cost precursor and strictly-controlled procedures. Herein, by virtue of the ul...Impeding high temperature sintering is challengeable for synthesis of carbon-supported single-atom catalysts (C-SACs), which requires high-cost precursor and strictly-controlled procedures. Herein, by virtue of the ultrastrong polarity of salt melts, sintering of metal atoms is effectively suppressed. Meanwhile, doping with inorganic sulfur anions not only produces sufficient anchoring sites to achieve high loading of atomically dispersed Co up to 13.85 wt.%, but also enables their electronic and geometric structures to be well tuned. When served as a cathode catalyst in dye-sensitized solar cells, the C-SAC with Co-N4-S2 moieties exhibits high activity towards the iodide reduction reaction (IRR), achieving a higher power conversion efficiency than that of conventional Pt counterpart. Density function theory (DFT) calculations revealed that the superior IRR activity was ascribed to the unique structure of Co-N4-S2 moieties with lower reaction barriers and moderate binding energy of iodine on the Co center, which was beneficial to I2 dissociation.展开更多
Highly photoluminescent nitrogen and sulfur co-doped carbon nanoparticles(CNPs) ca. 56 nm have been prepared through a green one-step hydrothermal synthesis route by using millet powder as carbon sources, in which t...Highly photoluminescent nitrogen and sulfur co-doped carbon nanoparticles(CNPs) ca. 56 nm have been prepared through a green one-step hydrothermal synthesis route by using millet powder as carbon sources, in which the nitrogen and sulfur co-doping improves the photoluminescent efficiency of the CNPs. The as-prepared CNPs display excellent fluorescent properties and low biotoxicity with a relatively high quantum yield of 30.4%, which have been applied for bioimaging and highly sensitive and selective detection of iron(III) ions.展开更多
Polypyrrole and sulfur derived hollow carbon nanofibers co-doped with nitrogen/sulfur are synthesized and applied as the anode for Na-ion batteries(NIBs). Successful doping of hollow carbon nanofiber with nitrogen and...Polypyrrole and sulfur derived hollow carbon nanofibers co-doped with nitrogen/sulfur are synthesized and applied as the anode for Na-ion batteries(NIBs). Successful doping of hollow carbon nanofiber with nitrogen and sulfur is confirmed by X-ray photoelectron spectroscopy, scanning and tunneling electron microscopy. Further analysis certifies that sulfur doping has a significant impact in improving the elecctrochemical performance of the carbon-based anodes for NIBs. The obtained N-doped hollow carbon nanofiber and N/S co-doped hollow carbon nanofiber exhibit similar morphologies but different electrochemical behavior. As expected, the N/S co-doped hollow carbon nanofiber anode exhibits enhanced electrochemical performance, including high specific capacity, outstanding long-term stability, and good rate stability.展开更多
Highly luminescent colloidal nanocrystals have wide applications in bioimaging and various optoelectronic devices.Herein we report a facile and mild procedure by combining S2-treatment and binary ligand passivation,wh...Highly luminescent colloidal nanocrystals have wide applications in bioimaging and various optoelectronic devices.Herein we report a facile and mild procedure by combining S2-treatment and binary ligand passivation,which can efficiently enhance the luminescent property of CdSe nanocrystals at room temperature.The photoluminescence quantum yield of as-treated CdSe nanocrystals exhibits drastic enhancement(e.g.,188 times for CdSe nanorods)after this dual-passivation treatment.The methodology proposed here can be applied to various CdSe nanocrystals,regardless of their sizes,shapes,and crystal structures.展开更多
To meet the ever-increasing energy demands, advanced electrode materials are strongly requested for the exploration of advanced energy storage and conversion technologies, such as Li-ion batteries, Li-S batteries, Li-...To meet the ever-increasing energy demands, advanced electrode materials are strongly requested for the exploration of advanced energy storage and conversion technologies, such as Li-ion batteries, Li-S batteries, Li-]Zn-air batteries, supercapacitors, dye-sensitized solar cells, and other electrocatalysis process (e.g., oxygen reductionlevolution reaction, hydrogen evolution reaction). Transition metal chalcogenides (TMCs, Le., sulfides and selenides) are forcefully considered as an emerging candidate, owing to their unique physical and chemical properties. Moreover, the integration of TMCs with conductive graphene host has enabled the significant improvement of electrochemical performance of devices. In this review, the recent research progress on TMC]graphene composites for applications in energy storage and conversion devices is summarized. The preparation process of TMC]graphene nanocomposites is also included. In order to promote an in-depth understanding of performance improvement for TMC/graphene materials, the operating principle of various devices and technologies are briefly presented. Finally, the perspectives are given on the design and construction of advanced electrode materials.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFA0402400)the National Natural Science Foundation of China(Grant Nos.11974358 and 11934004)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB34020000)the Heavy Ion Research Facility in Lanzhou(HIRFL).
文摘The state-selective cross section data are useful for understanding and modeling the x-ray emission in celestial observations.In the present work,using the cold target recoil ion momentum spectroscopy,for the first time we investigated the state-selective single electron capture processes for S^(q+)–He and H_(2)(q=11–15)collision systems at an impact energy of q×20 keV and obtained the relative state-selective cross sections.The results indicate that only a few principal quantum states of the projectile energy level are populated in a single electron capture process.In particular,the increase of the projectile charge state leads to the population of the states with higher principal quantum numbers.It is also shown that the experimental averaged n-shell populations are reproduced well by the over-barrier model.The database is openly available in Science Data Bank at 10.57760/sciencedb.j00113.00091.
基金supported in part by the Project of International Cooperation between China and Ukraine(043-05)the National Natural Science Foundation(No.20475044)the Invention Project of Science&Technology(KJCXGC-01,NWNU),China.
文摘A highly sensitive method is developed for the determination of trace amounts of some heavy metal ions in aqueous solution based on the classical Belousov-Zhabotinskii (BZ) oscillating chemical system. Introducing of S^2- ion makes the new oscillating system Ce(SO4)2 - KBrO3 - CH2(COOH)2 - Na2S - H2SO4 have to a high sensitivity for some heavy metal ions such as Ag^+, Pb^2+, Hg^2+, Cd^2+, Cu^2+and Bi^3+ with detection limits down to 10^-12 mol·L^- 1
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51773025 and 21701168)the Natural Foundation of Liaoning Province(Materials Joint Foundation,No.20180510027)+1 种基金Dalian Science and Technology Innovation Fund(No.019J12GX032)We gratefully acknowledge the BL14W1 Beamline of Shanghai Synchrotron Radiation Facility(SSRF)in Shanghai,China and the 1W1B Beamline of Beijing Synchrotron Radiation Facility(BSRF)in Beijing,China for providing the beam time.
文摘Impeding high temperature sintering is challengeable for synthesis of carbon-supported single-atom catalysts (C-SACs), which requires high-cost precursor and strictly-controlled procedures. Herein, by virtue of the ultrastrong polarity of salt melts, sintering of metal atoms is effectively suppressed. Meanwhile, doping with inorganic sulfur anions not only produces sufficient anchoring sites to achieve high loading of atomically dispersed Co up to 13.85 wt.%, but also enables their electronic and geometric structures to be well tuned. When served as a cathode catalyst in dye-sensitized solar cells, the C-SAC with Co-N4-S2 moieties exhibits high activity towards the iodide reduction reaction (IRR), achieving a higher power conversion efficiency than that of conventional Pt counterpart. Density function theory (DFT) calculations revealed that the superior IRR activity was ascribed to the unique structure of Co-N4-S2 moieties with lower reaction barriers and moderate binding energy of iodine on the Co center, which was beneficial to I2 dissociation.
基金financial supports of the National Natural Science Foundation of China(No.21535006)the Fundamental Research Funds for the Central Universities(No.XDJK2015B029)
文摘Highly photoluminescent nitrogen and sulfur co-doped carbon nanoparticles(CNPs) ca. 56 nm have been prepared through a green one-step hydrothermal synthesis route by using millet powder as carbon sources, in which the nitrogen and sulfur co-doping improves the photoluminescent efficiency of the CNPs. The as-prepared CNPs display excellent fluorescent properties and low biotoxicity with a relatively high quantum yield of 30.4%, which have been applied for bioimaging and highly sensitive and selective detection of iron(III) ions.
基金supported by the National Natural Science Foundation of China (51374255 and 51302323)Program for New Century Excellent Talents in University (NCET-13-0594)+2 种基金Research Fund for the Doctoral Program of Higher Education of China (201301621200)the Natural Science Foundation of Hunan Province, China (14JJ3018)the Exploration and Innovation Foundation of CSU for Postgraduate (502200568)
文摘Polypyrrole and sulfur derived hollow carbon nanofibers co-doped with nitrogen/sulfur are synthesized and applied as the anode for Na-ion batteries(NIBs). Successful doping of hollow carbon nanofiber with nitrogen and sulfur is confirmed by X-ray photoelectron spectroscopy, scanning and tunneling electron microscopy. Further analysis certifies that sulfur doping has a significant impact in improving the elecctrochemical performance of the carbon-based anodes for NIBs. The obtained N-doped hollow carbon nanofiber and N/S co-doped hollow carbon nanofiber exhibit similar morphologies but different electrochemical behavior. As expected, the N/S co-doped hollow carbon nanofiber anode exhibits enhanced electrochemical performance, including high specific capacity, outstanding long-term stability, and good rate stability.
基金financial support from the National Natural Science Foundation of China (NSFC,Nos.21872038 and 21733003)MOST (No.2017YFA0207303)Key Basic Research Program of Science and Technology Commission of Shanghai Municipality (No.17JC1400100)
文摘Highly luminescent colloidal nanocrystals have wide applications in bioimaging and various optoelectronic devices.Herein we report a facile and mild procedure by combining S2-treatment and binary ligand passivation,which can efficiently enhance the luminescent property of CdSe nanocrystals at room temperature.The photoluminescence quantum yield of as-treated CdSe nanocrystals exhibits drastic enhancement(e.g.,188 times for CdSe nanorods)after this dual-passivation treatment.The methodology proposed here can be applied to various CdSe nanocrystals,regardless of their sizes,shapes,and crystal structures.
基金supported by the National Key Research and Development Program(Nos.2016YFA0202500,2016YFA0200102)the National Natural Science Foundation of China(No.21676160)China Postdoctoral Science Foundation(No.2017M620049)
文摘To meet the ever-increasing energy demands, advanced electrode materials are strongly requested for the exploration of advanced energy storage and conversion technologies, such as Li-ion batteries, Li-S batteries, Li-]Zn-air batteries, supercapacitors, dye-sensitized solar cells, and other electrocatalysis process (e.g., oxygen reductionlevolution reaction, hydrogen evolution reaction). Transition metal chalcogenides (TMCs, Le., sulfides and selenides) are forcefully considered as an emerging candidate, owing to their unique physical and chemical properties. Moreover, the integration of TMCs with conductive graphene host has enabled the significant improvement of electrochemical performance of devices. In this review, the recent research progress on TMC]graphene composites for applications in energy storage and conversion devices is summarized. The preparation process of TMC]graphene nanocomposites is also included. In order to promote an in-depth understanding of performance improvement for TMC/graphene materials, the operating principle of various devices and technologies are briefly presented. Finally, the perspectives are given on the design and construction of advanced electrode materials.