The structures and electrochemical properties of the Ti1.4V0.6Ni ribbon before and after heat treatment are investigated systematically. The structure of the sample is characterized by X-ray powder diffraction analysi...The structures and electrochemical properties of the Ti1.4V0.6Ni ribbon before and after heat treatment are investigated systematically. The structure of the sample is characterized by X-ray powder diffraction analysis. Electrochemical properties including the discharge capacity, the cyclic stability and the high-rate discharge ability are tested. X-ray powder diffraction analysis shows that after heat treatment at 590 °C for 30 min, all samples mainly consist of the icosahedral quasicrystal phase (I-phase), Ti2Ni phase (FCC), V-based solid solution phase (BCC) and C14 Laves phase (hexagonal). Electrochemical measurements show that the maximum discharge capacity of the alloy electrode after heat treatment is 330.9 mA?h/g under the conditions that the discharge current density is 30 mA/g and the temperature is 30 °C. The result indicates that the cyclic stability and the high-rate discharge ability are all improved. In addition, the electrochemical kinetics of the alloy electrode is also studied by electrochemical impedance spectroscopy (EIS) and hydrogen diffusion coefficient (D).展开更多
Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(M...Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(MOF),namely ECUT-60,which renders not only high chemical stability,but also unique structure with multiple traps.This leads to the ultrahigh Xe adsorption capacity,exceeding most reported porous materials.Impressively,this MOF also enables high selectivity of Xe over Kr,CO2,O2,and N2,leading to the high-performance separation for trace quantitites of Xe/Kr from a simulated UNF reprocessing off-gas.The separation capability has been demonstrated by using dynamic breakthrough experiments,giving the record Xe uptake up to 70.4 mmol/kg and the production of 19.7 mmol/kg pure Xe.Consequently,ECUT-60 has promising potential in direct production of Xe from UNF off-gas or air.The separation mechanism,as unveiled by theoretical calculation,is attributed to the multiple traps in ECUT-60 that affords rigid restrict for Xe atom via van der Waals force.展开更多
The practical application of high-energy lithium–sulfur battery is plagued with two deadly obstacles.One is the“shuttle effect”originated from the sulfur cathode,and the other is the low Coulombic efficiency and se...The practical application of high-energy lithium–sulfur battery is plagued with two deadly obstacles.One is the“shuttle effect”originated from the sulfur cathode,and the other is the low Coulombic efficiency and security issues arising from the lithium metal anode.In addressing these issues,we propose a novel silicon-sulfurized poly(acrylonitrile)full battery.In this lithium metal-free system,the Li source is pre-loaded in the cathode,using a nitrogen evolution reaction(NER)to implant Li+into the silicon/carbon anode.Sulfurized poly(acrylonitrile)based on a solid–solid conversion mechanism can fundamentally circumvent the“shuttle effect”.Meanwhile,the silicon/carbon anode can achieve more efficient utiliza-tion and higher security when compared with the Li metal anode.The full cell used in this technology can deliver a capacity of 1169.3 mAh g^(-1),and it can be stabilized over 100 cycles,implying its excellent elec-trochemical stability.Furthermore,the practical pouch cell with a high sulfur loading of 4.2 mg cm^(-2)can achieve a high specific energy of 513.2 Wh kg-1.The mechanism of the NER in cathode has also been investigated and analyzed by in situ methods.Notably,this battery design completely conforms to the current battery production technology because of the degassing of gasbag,resulting in a low manufactur-ing cost.This work will open the avenue to develop a lithium metal-free battery using the NER.展开更多
基金Project (20112216120001) supported by the Doctoral Program of Tertiary Education of the Ministry of Education of ChinaProject(21215141) supported by the Natural Science Foundation of Jilin Province, China+3 种基金Project (20921002) supported by the Foundation for Innovative Research Groups of the National Natural Science Foundation of ChinaProjects (21073179, 61106050) supported by the National Natural Science Foundation of ChinaProject (BE2012047) supported by Scientific and Technological Supporting Program of Jiangsu Province of China and GS Yuasa Corporation of JapanProject (11KZ38) supported by and Scientific and Technological Pillar Project of Changchun, China
文摘The structures and electrochemical properties of the Ti1.4V0.6Ni ribbon before and after heat treatment are investigated systematically. The structure of the sample is characterized by X-ray powder diffraction analysis. Electrochemical properties including the discharge capacity, the cyclic stability and the high-rate discharge ability are tested. X-ray powder diffraction analysis shows that after heat treatment at 590 °C for 30 min, all samples mainly consist of the icosahedral quasicrystal phase (I-phase), Ti2Ni phase (FCC), V-based solid solution phase (BCC) and C14 Laves phase (hexagonal). Electrochemical measurements show that the maximum discharge capacity of the alloy electrode after heat treatment is 330.9 mA?h/g under the conditions that the discharge current density is 30 mA/g and the temperature is 30 °C. The result indicates that the cyclic stability and the high-rate discharge ability are all improved. In addition, the electrochemical kinetics of the alloy electrode is also studied by electrochemical impedance spectroscopy (EIS) and hydrogen diffusion coefficient (D).
基金supported by the National Natural Science Foundation of China (22005293, U19A2092 and 22275180)the National Key Research and Development Program of China (2019YFA0405600)+1 种基金the Institute of Energy, Hefei Comprehensive National Science Center (21KZS212)the Collaborative Innovation Program of Hefei Science Center, CAS。
基金supported by the National Natural Science Foundations of China(21966002 and 21871047)the Natural Science Foundation of Jiangxi Province(20181ACB20003)+1 种基金the Training Program for Academic and Technical Leaders of Major Disciplines in Jiangxi Province(20194BCJ22010)the Graduate Innovation Project of East China University of Technology(DHYC-202023)。
文摘Direct separation of Xe and Kr from air or used nuclear fuel(UNF)off-gas by means of porous adsorbents is of industrial importance but is a very challenging task.In this work,we show a robust metal-organic framework(MOF),namely ECUT-60,which renders not only high chemical stability,but also unique structure with multiple traps.This leads to the ultrahigh Xe adsorption capacity,exceeding most reported porous materials.Impressively,this MOF also enables high selectivity of Xe over Kr,CO2,O2,and N2,leading to the high-performance separation for trace quantitites of Xe/Kr from a simulated UNF reprocessing off-gas.The separation capability has been demonstrated by using dynamic breakthrough experiments,giving the record Xe uptake up to 70.4 mmol/kg and the production of 19.7 mmol/kg pure Xe.Consequently,ECUT-60 has promising potential in direct production of Xe from UNF off-gas or air.The separation mechanism,as unveiled by theoretical calculation,is attributed to the multiple traps in ECUT-60 that affords rigid restrict for Xe atom via van der Waals force.
基金the National Natural Science Foundation of China(21922508,21673116,21633003,and U1801251)Natural Science Foundation of Jiangsu Province of China(BK20190009)and Key R&D Project funded by Department of Science and Technology of Jiangsu Province(BE2020003)。
文摘The practical application of high-energy lithium–sulfur battery is plagued with two deadly obstacles.One is the“shuttle effect”originated from the sulfur cathode,and the other is the low Coulombic efficiency and security issues arising from the lithium metal anode.In addressing these issues,we propose a novel silicon-sulfurized poly(acrylonitrile)full battery.In this lithium metal-free system,the Li source is pre-loaded in the cathode,using a nitrogen evolution reaction(NER)to implant Li+into the silicon/carbon anode.Sulfurized poly(acrylonitrile)based on a solid–solid conversion mechanism can fundamentally circumvent the“shuttle effect”.Meanwhile,the silicon/carbon anode can achieve more efficient utiliza-tion and higher security when compared with the Li metal anode.The full cell used in this technology can deliver a capacity of 1169.3 mAh g^(-1),and it can be stabilized over 100 cycles,implying its excellent elec-trochemical stability.Furthermore,the practical pouch cell with a high sulfur loading of 4.2 mg cm^(-2)can achieve a high specific energy of 513.2 Wh kg-1.The mechanism of the NER in cathode has also been investigated and analyzed by in situ methods.Notably,this battery design completely conforms to the current battery production technology because of the degassing of gasbag,resulting in a low manufactur-ing cost.This work will open the avenue to develop a lithium metal-free battery using the NER.
