The use of TiO2 as an anode in rechargeable sodium-ion batteries(NIBs)is hampered by intrinsic low electronic conductivity of TiO2 and in ferior electrode kinetics.Here,a high-performa nee T1O2 electrode for NIBs is p...The use of TiO2 as an anode in rechargeable sodium-ion batteries(NIBs)is hampered by intrinsic low electronic conductivity of TiO2 and in ferior electrode kinetics.Here,a high-performa nee T1O2 electrode for NIBs is prese nted by desig ning a multicha rinel porous T1O2 nano fibers with well-dispersed Cu nan odots and Cu^2+-doping derived oxyge n vaca ncies(Cu-MPTO).The in-situ grow n well-dispersed copper nano dots of about 3 nm on TiO2 surface could significantly enhance electronic conductivity of the TiO2 fibers.The one-dimensional multichannel porous structure could facilitate the electrolyte to soak in,leadi ng to short tran sport path of Na^+through carb on toward the TiO2 nano particle.The Cu^2+-doping induced oxygen vacancies could decrease the bandgap of T1O2,resulting in easy electron trapping.With this strategy,the Cu-MPTO electrodes render an outstanding rate performance for NIBs(120 mAh·g^-1 at 20 C)and a superior cycling stability for ultralong cycle life(120 mAh·g^-1 at 20 C and 96.5%retention over 2,000 cycles).Density functional theory(DFT)calculations also suggest that Cu^2+doping can enhance the conductivity and electron transfer of T1O2 and lower the sodiation energy barrier.This strategy is confirmed to be a general process and could be extended to improve the performance of other materials with low electronic conductivity applied in energy storage systems.展开更多
Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe an...Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe and N doping porous carb on n ematosphere(FeNPCN)as an excellent CO2RR electrocatalyst in aqueous electrolyte.Featuring with the high conductivity,pore structure and abundant Fe and N doping,FeNPCN exhibits high catalytic activity with a high faradaic selectivity of CO(94%)and long-term durability.Moreover,the ratio of CO and H2 can be changed by the applied potential for the different syngas related industry.Density functional theory(DFT)calculation results also reveal that the excellent catalytic activity is likely attributed to C and N hybrid coordination with atomic Fe.展开更多
基金This work was supported by the National Key R&D Research Program of China(Nos.2018YFB0905400 and 2016YFB0100305)the National Natural Science Foundation of China(Nos.51622210 and 51872277)+1 种基金the Fundamental Research Funds for the Central Univers让ies(No.WK3430000004)the DNL cooperation Fund,CAS(No.DNL180310).
文摘The use of TiO2 as an anode in rechargeable sodium-ion batteries(NIBs)is hampered by intrinsic low electronic conductivity of TiO2 and in ferior electrode kinetics.Here,a high-performa nee T1O2 electrode for NIBs is prese nted by desig ning a multicha rinel porous T1O2 nano fibers with well-dispersed Cu nan odots and Cu^2+-doping derived oxyge n vaca ncies(Cu-MPTO).The in-situ grow n well-dispersed copper nano dots of about 3 nm on TiO2 surface could significantly enhance electronic conductivity of the TiO2 fibers.The one-dimensional multichannel porous structure could facilitate the electrolyte to soak in,leadi ng to short tran sport path of Na^+through carb on toward the TiO2 nano particle.The Cu^2+-doping induced oxygen vacancies could decrease the bandgap of T1O2,resulting in easy electron trapping.With this strategy,the Cu-MPTO electrodes render an outstanding rate performance for NIBs(120 mAh·g^-1 at 20 C)and a superior cycling stability for ultralong cycle life(120 mAh·g^-1 at 20 C and 96.5%retention over 2,000 cycles).Density functional theory(DFT)calculations also suggest that Cu^2+doping can enhance the conductivity and electron transfer of T1O2 and lower the sodiation energy barrier.This strategy is confirmed to be a general process and could be extended to improve the performance of other materials with low electronic conductivity applied in energy storage systems.
基金This work was financially supported the National Natural Science Foundation of China(Nos.21725103,51522101,51471075,51631004,51472232,51522202 and 21771013)Program for JLU Science and Technology Innovative Research Team(No.2017TD-09).
文摘Carbon dioxide reduction(CO2RR)has become a promising way to address the energy and environmental crisis,of which the fundamental development of the optimal electrocatalysts is the crucial part.Herein,we develop Fe and N doping porous carb on n ematosphere(FeNPCN)as an excellent CO2RR electrocatalyst in aqueous electrolyte.Featuring with the high conductivity,pore structure and abundant Fe and N doping,FeNPCN exhibits high catalytic activity with a high faradaic selectivity of CO(94%)and long-term durability.Moreover,the ratio of CO and H2 can be changed by the applied potential for the different syngas related industry.Density functional theory(DFT)calculation results also reveal that the excellent catalytic activity is likely attributed to C and N hybrid coordination with atomic Fe.