Zinc telluride(ZnTe)with high density and low cost is considered as promising anode for sodium-ion batteries.However,ZnTe suffers from continuous capacity degradation owing to the low electronic conductivity,large vol...Zinc telluride(ZnTe)with high density and low cost is considered as promising anode for sodium-ion batteries.However,ZnTe suffers from continuous capacity degradation owing to the low electronic conductivity,large volume expansion,and high ion-diffusion energy barriers.Herein,the nitrogen-doped carbon confined ZnTe polyhedron heterostructure(ZnTe/NC)is proposed,exploiting its orbital rehybridization and the realignment of energy level to improve storage performance.Systematic ex situ/in situ characterizations and simulations demonstrated that the elaborate ZnTe/NC offers abundant electron/ion transport pathways,accelerates Na^(+)diffusion kinetics,and alleviates huge volume expansion.Notably,the nitrogen-doped carbon-support interaction induced via electron transfer between ZnTe sites and support elevates the energy level of Zn 3d orbital,greatly enhancing ion adsorption capability and reducing the ion diffusion barrier.As a result,the ZnTe/NC anode delivers a high discharge capacity of 470.5 mAh g^(−1)and long cycling durability over 1000 cycles.This work uncovers that optimizing sodium ion adsorption and diffusion via d-orbital energy level modulation enabled by nitrogen-doped support interaction is an effective method for developing high-performance transition metal telluride anodes for alkali ion storage.展开更多
Calcium carboaluminate was successfully prepared by a simple and efficient one-step method,and the effects of temperature,time,raw material ratio,carbonate type and heavy CaCO_(3)particle size on the products were inv...Calcium carboaluminate was successfully prepared by a simple and efficient one-step method,and the effects of temperature,time,raw material ratio,carbonate type and heavy CaCO_(3)particle size on the products were investigated in detail.The results show that increasing the temperature and extending the reaction time can enhance the yield and crystallisation degree of calcium carboaluminate.The proportion of Ca(OH)_(2),Al(OH)_(3)and CaCO_(3)is a pivotal factor in the synthesis of calcium carboaluminate.When the ratio of Ca(OH)_(2),Al(OH)_(3)and CaCO_(3)is 3:2:1,the diffraction peaks of calcium carboaluminate in the products are relatively sharp and strong.Furthermore,the purity and crystallinity of the synthesized calcium carboaluminate are higher when heavy CaCO_(3)with the particle size of 120 mesh is used as the carbonate raw material,in comparison to CO_(2),Na_(2)CO_(3)and light CaCO_(3).As results,a simple and efficient method for the synthesis of calcium carboaluminate is proposed,which will provide a solid experimental foundation and technical support for the industrial application of calcium carboaluminate in marine concrete.展开更多
基金supported by the National Natural Science Foundation of China(52402298,52172224,52302240)Science and Technology Correspondent Project of Tianjin(24YDTPJC00240)+1 种基金the Macao Young Scholars Program(AM2023011)the Yuanguang Scholars Program,Hebei University of Technology(282022554).
文摘Zinc telluride(ZnTe)with high density and low cost is considered as promising anode for sodium-ion batteries.However,ZnTe suffers from continuous capacity degradation owing to the low electronic conductivity,large volume expansion,and high ion-diffusion energy barriers.Herein,the nitrogen-doped carbon confined ZnTe polyhedron heterostructure(ZnTe/NC)is proposed,exploiting its orbital rehybridization and the realignment of energy level to improve storage performance.Systematic ex situ/in situ characterizations and simulations demonstrated that the elaborate ZnTe/NC offers abundant electron/ion transport pathways,accelerates Na^(+)diffusion kinetics,and alleviates huge volume expansion.Notably,the nitrogen-doped carbon-support interaction induced via electron transfer between ZnTe sites and support elevates the energy level of Zn 3d orbital,greatly enhancing ion adsorption capability and reducing the ion diffusion barrier.As a result,the ZnTe/NC anode delivers a high discharge capacity of 470.5 mAh g^(−1)and long cycling durability over 1000 cycles.This work uncovers that optimizing sodium ion adsorption and diffusion via d-orbital energy level modulation enabled by nitrogen-doped support interaction is an effective method for developing high-performance transition metal telluride anodes for alkali ion storage.
基金Funded by the National Nature Science Foundation of China(No.52078321)。
文摘Calcium carboaluminate was successfully prepared by a simple and efficient one-step method,and the effects of temperature,time,raw material ratio,carbonate type and heavy CaCO_(3)particle size on the products were investigated in detail.The results show that increasing the temperature and extending the reaction time can enhance the yield and crystallisation degree of calcium carboaluminate.The proportion of Ca(OH)_(2),Al(OH)_(3)and CaCO_(3)is a pivotal factor in the synthesis of calcium carboaluminate.When the ratio of Ca(OH)_(2),Al(OH)_(3)and CaCO_(3)is 3:2:1,the diffraction peaks of calcium carboaluminate in the products are relatively sharp and strong.Furthermore,the purity and crystallinity of the synthesized calcium carboaluminate are higher when heavy CaCO_(3)with the particle size of 120 mesh is used as the carbonate raw material,in comparison to CO_(2),Na_(2)CO_(3)and light CaCO_(3).As results,a simple and efficient method for the synthesis of calcium carboaluminate is proposed,which will provide a solid experimental foundation and technical support for the industrial application of calcium carboaluminate in marine concrete.
