Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materia...Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materials to obtain satisfactory performance at low-to-moderate overpotentials.Herein,a simple and facile electrospinning technique is utilized to prepare a composite of a bimetallic Sn-Co oxide/carbon matrix with a hollow nanotube structure(Sn Co-HNT).Sn Co-HNT can maintain>90%faradaic efficiencies for C1 products within a wide potential range from-0.6 VRHE to-1.2 VRHE,and a highest 94.1%selectivity towards CO in an H-type cell.Moreover,a 91.2%faradaic efficiency with a 241.3 m A cm^(-2)partial current density for C1 products could be achieved using a flow cell.According to theoretical calculations,the fusing of Sn/Co oxides on the carbon matrix accelerates electron transfer at the atomic level,causing electron deficiency of Sn centers and reversible variation between Co^(2+)and Co^(3+)centers.The synergistic effect of the Sn/Co composition improves the electron affinity of the catalyst surface,which is conducive to the adsorption and stabilization of key intermediates and eventually increases the catalytic activity in CO_(2)electroreduction.This study could provide a new strategy for the construction of oxide-derived catalysts for CO_(2)electroreduction.展开更多
Silicon monoxide(SiO)has aroused increased attention as one of the most promising anodes for high-energy density Li-ion batteries.To enhance the initial Coulombic efficiencies(ICE)and cycle stability of SiO-based anod...Silicon monoxide(SiO)has aroused increased attention as one of the most promising anodes for high-energy density Li-ion batteries.To enhance the initial Coulombic efficiencies(ICE)and cycle stability of SiO-based anodes,a new facile composition and electrode design strategy have been adapted to fabricate a SiO-Sn-Co/graphite(G)anode.It achieves a unique structure where tiny milled SiO-Sn-Co particles are dispersed among two graphite layers.In this hybrid electrode,Sn-Co alloys promoted Li;extraction kinetics,and the holistic reversibility of SiO and graphite enhanced the electrical conductivity.The SiO-Sn-Co/G electrode delivered an average ICE of 77.6%and a reversible capacity of 640 mAh g^(-1)at 800 mA g^(-1),and the capacity retention was above 98%after 100 cycles,which was much higher than that of the SiO with an ICE of 55.3%and a capacity retention of 50%.These results indicated that this was reliable method to improve the reversibility and cycle ability of the SiO anode.Furthermore,based on its easy and feasible fabrication process,it may provide a suitable choice to combine other alloy anodes with the graphite anode.展开更多
基金supported by the National Natural Science Foundation of China(U21A20312,22172099,21975162,51902209)the Natural Science Foundation of Guangdong(2020A1515010840)the Shenzhen Science and Technology Program(SGDX20201103095802006,RCBS20200714114819161,JCYJ20190808111801674,JCYJ20200109105803806,RCYX20200714114535052)。
文摘Earth-abundant and nontoxic Sn-based materials have been regarded as promising catalysts for the electrochemical conversion of CO_(2)to C1 products,e.g.,CO and formate.However,it is still difficult for Snbased materials to obtain satisfactory performance at low-to-moderate overpotentials.Herein,a simple and facile electrospinning technique is utilized to prepare a composite of a bimetallic Sn-Co oxide/carbon matrix with a hollow nanotube structure(Sn Co-HNT).Sn Co-HNT can maintain>90%faradaic efficiencies for C1 products within a wide potential range from-0.6 VRHE to-1.2 VRHE,and a highest 94.1%selectivity towards CO in an H-type cell.Moreover,a 91.2%faradaic efficiency with a 241.3 m A cm^(-2)partial current density for C1 products could be achieved using a flow cell.According to theoretical calculations,the fusing of Sn/Co oxides on the carbon matrix accelerates electron transfer at the atomic level,causing electron deficiency of Sn centers and reversible variation between Co^(2+)and Co^(3+)centers.The synergistic effect of the Sn/Co composition improves the electron affinity of the catalyst surface,which is conducive to the adsorption and stabilization of key intermediates and eventually increases the catalytic activity in CO_(2)electroreduction.This study could provide a new strategy for the construction of oxide-derived catalysts for CO_(2)electroreduction.
基金supported by the National Natural Science Foundation of China (No. 52071144, 51822104, 51831009, and 51621001)
文摘Silicon monoxide(SiO)has aroused increased attention as one of the most promising anodes for high-energy density Li-ion batteries.To enhance the initial Coulombic efficiencies(ICE)and cycle stability of SiO-based anodes,a new facile composition and electrode design strategy have been adapted to fabricate a SiO-Sn-Co/graphite(G)anode.It achieves a unique structure where tiny milled SiO-Sn-Co particles are dispersed among two graphite layers.In this hybrid electrode,Sn-Co alloys promoted Li;extraction kinetics,and the holistic reversibility of SiO and graphite enhanced the electrical conductivity.The SiO-Sn-Co/G electrode delivered an average ICE of 77.6%and a reversible capacity of 640 mAh g^(-1)at 800 mA g^(-1),and the capacity retention was above 98%after 100 cycles,which was much higher than that of the SiO with an ICE of 55.3%and a capacity retention of 50%.These results indicated that this was reliable method to improve the reversibility and cycle ability of the SiO anode.Furthermore,based on its easy and feasible fabrication process,it may provide a suitable choice to combine other alloy anodes with the graphite anode.
