Li metal anode holds great promise to realize high-energy battery systems.However,the safety issue and limited lifetime caused by the uncontrollable growth of Li dendrites hinder its commercial application.Herein,an i...Li metal anode holds great promise to realize high-energy battery systems.However,the safety issue and limited lifetime caused by the uncontrollable growth of Li dendrites hinder its commercial application.Herein,an interlayer-bridged 3D lithiophilic rGO-Ag-S-CNT composite is proposed to guide uniform and stable Li plating/stripping.The 3D lithiophilic rGO-Ag-S-CNT host is fabricated by incorporating Ag-modified reduced graphene oxide(rGO)with S-doped carbon nanotube(CNT),where the rGO and CNT are closely connected via robust Ag-S covalent bond.This strong Ag-S bond could enhance the structural stability and electrical connection between rGO and CNT,significantly improving the electrochemical kinetics and uniformity of current distribution.Moreover,density functional theory calculation indicates that the introduction of Ag-S bond could further boost the binding energy between Ag and Li,which promotes homogeneous Li nucleation and growth.Consequently,the rGO-Ag-S-CNT-based anode achieves a lower overpotential(7.3 mV at 0.5 mA cm^(−2)),higher Coulombic efficiency(98.1%at 0.5 mA cm^(−2)),and superior long cycling performance(over 500 cycles at 2 mA cm−2)as compared with the rGO-Ag-CNT-and rGO-CNT-based anodes.This work provides a universal avenue and guidance to build a robust Li metal host via constructing a strong covalent bond,effectively suppressing the Li dendrites growth to prompt the development of Li metal battery.展开更多
High-performance composites containing various kinds of nanofibers as reinforcing building blocks have recently received considerable attention, owing to their superior mechanical properties. One of the effective stra...High-performance composites containing various kinds of nanofibers as reinforcing building blocks have recently received considerable attention, owing to their superior mechanical properties. One of the effective strategies to reinforce these composites involves strengthening interfacial interactions via covalent bonds. However, in contrast to nanosheets, covalent bonds have been rarely used in nanofiber-reinforced composites. Herein, we report the macroscale fabrication of a series of Ag nanowire （NW）-thiolated chitosan （TCS） composite films via spray induced self-assembly. The obtained films were significantly strengthened by Ag-S covalent bonds formed between the Ag NWs and the thiol groups of TCS. The tensile strength of the optimized Ag NW-TCS film was up to 3.9 and 1.5 times higher compared with that of pure TCS and Ag NW-chitosan （CS） films, respectively.展开更多
基金This work is supported by Singapore Ministry of Education academic research grant Tier 2 (MOE2019-T2-1-181).
文摘Li metal anode holds great promise to realize high-energy battery systems.However,the safety issue and limited lifetime caused by the uncontrollable growth of Li dendrites hinder its commercial application.Herein,an interlayer-bridged 3D lithiophilic rGO-Ag-S-CNT composite is proposed to guide uniform and stable Li plating/stripping.The 3D lithiophilic rGO-Ag-S-CNT host is fabricated by incorporating Ag-modified reduced graphene oxide(rGO)with S-doped carbon nanotube(CNT),where the rGO and CNT are closely connected via robust Ag-S covalent bond.This strong Ag-S bond could enhance the structural stability and electrical connection between rGO and CNT,significantly improving the electrochemical kinetics and uniformity of current distribution.Moreover,density functional theory calculation indicates that the introduction of Ag-S bond could further boost the binding energy between Ag and Li,which promotes homogeneous Li nucleation and growth.Consequently,the rGO-Ag-S-CNT-based anode achieves a lower overpotential(7.3 mV at 0.5 mA cm^(−2)),higher Coulombic efficiency(98.1%at 0.5 mA cm^(−2)),and superior long cycling performance(over 500 cycles at 2 mA cm−2)as compared with the rGO-Ag-CNT-and rGO-CNT-based anodes.This work provides a universal avenue and guidance to build a robust Li metal host via constructing a strong covalent bond,effectively suppressing the Li dendrites growth to prompt the development of Li metal battery.
文摘High-performance composites containing various kinds of nanofibers as reinforcing building blocks have recently received considerable attention, owing to their superior mechanical properties. One of the effective strategies to reinforce these composites involves strengthening interfacial interactions via covalent bonds. However, in contrast to nanosheets, covalent bonds have been rarely used in nanofiber-reinforced composites. Herein, we report the macroscale fabrication of a series of Ag nanowire （NW）-thiolated chitosan （TCS） composite films via spray induced self-assembly. The obtained films were significantly strengthened by Ag-S covalent bonds formed between the Ag NWs and the thiol groups of TCS. The tensile strength of the optimized Ag NW-TCS film was up to 3.9 and 1.5 times higher compared with that of pure TCS and Ag NW-chitosan （CS） films, respectively.
