Silicon nanowires(SiNWs) encapsulated with graphene-like carbon sheath(GS) having a void space in between(SiNW@V@GS) are demonstrated for the improved electrochemical performance of Si anode in lithium ion batte...Silicon nanowires(SiNWs) encapsulated with graphene-like carbon sheath(GS) having a void space in between(SiNW@V@GS) are demonstrated for the improved electrochemical performance of Si anode in lithium ion battery. The Si NW@V@GS structure was synthesized by a scalable fabrication method including four successive reactions: metal-catalyzed CVD growth of Si NWs, controlled thermal oxidation, and deposition of the graphitic layer, to form Si NW@SiO2@GS and additional chemical etching of sacrificial SiO2 layer between Si NWs and carbon sheath. During the synthetic process, the thickness of the void spacing was controlled by adjusting the oxidation-dependent process. The well-controlled void space and crystalline graphitic carbon sheath of the SiNW@V@GS structure enable good reversible capacity of1444 m Ahg^(-1) and cycling stability of 85% over 150 cycles.展开更多
基金supported by the “Human Resources Program in Energy Technology” of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) the granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20154030200870)
文摘Silicon nanowires(SiNWs) encapsulated with graphene-like carbon sheath(GS) having a void space in between(SiNW@V@GS) are demonstrated for the improved electrochemical performance of Si anode in lithium ion battery. The Si NW@V@GS structure was synthesized by a scalable fabrication method including four successive reactions: metal-catalyzed CVD growth of Si NWs, controlled thermal oxidation, and deposition of the graphitic layer, to form Si NW@SiO2@GS and additional chemical etching of sacrificial SiO2 layer between Si NWs and carbon sheath. During the synthetic process, the thickness of the void spacing was controlled by adjusting the oxidation-dependent process. The well-controlled void space and crystalline graphitic carbon sheath of the SiNW@V@GS structure enable good reversible capacity of1444 m Ahg^(-1) and cycling stability of 85% over 150 cycles.