A high-efficiency method is developed to in-situ synthesize nanocrystalline TiC powders,nanorods,and nanosheets by using equimolar ratio of Ti powder and acetylene black,multiwalled carbon nanotubes(MWCNTs),and graphe...A high-efficiency method is developed to in-situ synthesize nanocrystalline TiC powders,nanorods,and nanosheets by using equimolar ratio of Ti powder and acetylene black,multiwalled carbon nanotubes(MWCNTs),and graphene,respectively,as precursor in eutectic Na Cl-KCl molten salt at 800–900℃for 2–3 h.Higher temperature and longer duration are more beneficial for TiC preparation.In addition,mechanism of TiC formation was investigated by linear scan voltammetry.Results indicate that nanocrystalline TiC is in-situ synthesized by reaction between Ti atoms,which come from disproportionation reaction of Ti(Ⅱ)species in the molten salt,and C atoms on the surface of carbon sources.展开更多
A simple method to synthesize high-content ternary carbide Ti3AlC2 nanoparticles from Ti,Al,and C starting elemental powders without ball milling in NaCl–KCl molten salt was reported.The effects of mass ratio of the ...A simple method to synthesize high-content ternary carbide Ti3AlC2 nanoparticles from Ti,Al,and C starting elemental powders without ball milling in NaCl–KCl molten salt was reported.The effects of mass ratio of the salt to starting materials,temperature,reaction time,and Al molar ratio on preparation of Ti3AlC2 were investigated.The Ti3AlC2 formation is dramatically influenced by temperature and mass ratio of the salt to raw materials:a higher temperature and higher mass ratio of the salt to raw materials are more preferable for Ti3AlC2 powder formation.Homogenous Ti3AlC2 powder with particle size of■nm is synthesized by 3Ti/Al/2C starting elemental powders in NaCl–KCl molten salt at 900℃for 10 h,950℃for 5h,or 1000℃for 2h,respectively,when the mass ratio of the salt to 3Ti/Al/2C starting materials is 10:1.展开更多
Transition metal nitrides(TMNs),including titanium nitride(TiN),exhibit remarkable application prospects as anodes for durable high-rate lithium-ion batteries(LIBs).Regrettably,the absence of simple synthesis methods ...Transition metal nitrides(TMNs),including titanium nitride(TiN),exhibit remarkable application prospects as anodes for durable high-rate lithium-ion batteries(LIBs).Regrettably,the absence of simple synthesis methods restricts their further development.Herein,a facile and low-cost molten salt synthesis strategy was proposed to prepare carbon-anchored TiN nanoparticles as an advanced anode material for LIBs with high rate capabilities.This nanosized TiN obtained is∼5 nm in size and well-distributed onto carbon plates,which could release a reversible capacity of∼381.5 mAh g^(−1)at 0.1 A g^(−1)after 250 cycles and∼141.5 mAh g^(−1)at 1.0 A g^(−1)after 1000 cycles.Furthermore,it was confirmed that the conversion reaction between TiN and Li-ions happened during the electrochemical reaction process,resulting in the formation of Li_(3)N and Ti.This unique microstructure attributed from TiN nanoparticles anchored by carbon could support the structural volume during cycling.This work highlights the method superiority of TiN prepared via a molten salt synthesis strategy as an anode for LIBs with impressive rate performances.展开更多
基金supported financially by the National Natural Science Foundation of China(Nos.51671204 and 51501205).
文摘A high-efficiency method is developed to in-situ synthesize nanocrystalline TiC powders,nanorods,and nanosheets by using equimolar ratio of Ti powder and acetylene black,multiwalled carbon nanotubes(MWCNTs),and graphene,respectively,as precursor in eutectic Na Cl-KCl molten salt at 800–900℃for 2–3 h.Higher temperature and longer duration are more beneficial for TiC preparation.In addition,mechanism of TiC formation was investigated by linear scan voltammetry.Results indicate that nanocrystalline TiC is in-situ synthesized by reaction between Ti atoms,which come from disproportionation reaction of Ti(Ⅱ)species in the molten salt,and C atoms on the surface of carbon sources.
基金supported financially by the National Natural Science Foundation of China(No.51501205).
文摘A simple method to synthesize high-content ternary carbide Ti3AlC2 nanoparticles from Ti,Al,and C starting elemental powders without ball milling in NaCl–KCl molten salt was reported.The effects of mass ratio of the salt to starting materials,temperature,reaction time,and Al molar ratio on preparation of Ti3AlC2 were investigated.The Ti3AlC2 formation is dramatically influenced by temperature and mass ratio of the salt to raw materials:a higher temperature and higher mass ratio of the salt to raw materials are more preferable for Ti3AlC2 powder formation.Homogenous Ti3AlC2 powder with particle size of■nm is synthesized by 3Ti/Al/2C starting elemental powders in NaCl–KCl molten salt at 900℃for 10 h,950℃for 5h,or 1000℃for 2h,respectively,when the mass ratio of the salt to 3Ti/Al/2C starting materials is 10:1.
基金This work is supported by National Natural Science Foundation of China(No.51671204)Guangdong Basic and Applied Basic Research Foundation,China(No.2019A1515110825).
文摘Transition metal nitrides(TMNs),including titanium nitride(TiN),exhibit remarkable application prospects as anodes for durable high-rate lithium-ion batteries(LIBs).Regrettably,the absence of simple synthesis methods restricts their further development.Herein,a facile and low-cost molten salt synthesis strategy was proposed to prepare carbon-anchored TiN nanoparticles as an advanced anode material for LIBs with high rate capabilities.This nanosized TiN obtained is∼5 nm in size and well-distributed onto carbon plates,which could release a reversible capacity of∼381.5 mAh g^(−1)at 0.1 A g^(−1)after 250 cycles and∼141.5 mAh g^(−1)at 1.0 A g^(−1)after 1000 cycles.Furthermore,it was confirmed that the conversion reaction between TiN and Li-ions happened during the electrochemical reaction process,resulting in the formation of Li_(3)N and Ti.This unique microstructure attributed from TiN nanoparticles anchored by carbon could support the structural volume during cycling.This work highlights the method superiority of TiN prepared via a molten salt synthesis strategy as an anode for LIBs with impressive rate performances.