The large volume expansion and rapid capacity attenuation of tin-based electrodes are the main factors limiting their commercial application.The reasonable design of electrode material structure is particularly import...The large volume expansion and rapid capacity attenuation of tin-based electrodes are the main factors limiting their commercial application.The reasonable design of electrode material structure is particularly important for improving its electrochemical performance.Herein,phosphorus-modified graphene encapsulated Sn_(6)O_(4)(OH)_(4)nanoparticles composite(P-Sn_(6)O_(4)(OH)_(4)@RGO)with crystalline-amorphous heterostructure has been successfully designed and prepared.The design of crystalline-amorphous structure has largely enhanced the active sites,and the construction of a graphene encapsulation structure has greatly alleviated volume expansion.Notably,P-Sn_(6)O_(4)(OH)_(4)@RGO obtained an excellent high-rate longterm cycling performance for lithium-ion batteries anode,reaching a high specific capacity of 970 m Ah/g at 1.0 A/g after 1450 cycles.This work demonstrates that restructuring the electrode material's structure and phase through phosphorus modification can effectively improve the electrochemical performance of tin-based electrode materials.展开更多
Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored com...Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored compared with the other hydrocarbon products from Cu-based electrocatalysts.In this work,an alkanethiolmodified Cu_(2)O nanowire array(OTT-Cu_(2)O) was constructed with asymmetric Cu sites consisting of paired Cu-O and Cu-S motifs to overcome previous limitations of C_(2)H_(5)OH electrosynthesis via CO_(2)RR pathway.This catalyst achieves a high Faradaic efficiency of 45 % for CO_(2)-to-C_(2)H_(5)OH conversion at 300 m A/cm^(2),representing a more than two-fold enhancement over the Cu_(2)O electrode.Mechanistic investigations reveal that the Cu-S site exhibits distinct C-binding capability that stabilizes key intermediates(^(*)OCH_(2) and ^(*)CO),in contrast to the O-affinitive Cu-O site.The asymmetric S-Cu-O configuration promotes thermodynamically favorable asymmetric C-C coupling between ^(*)CO and ^(*)OCH_(2),forming the critical CO-OCH_(2) intermediate and facilitating C_(2)H_(5)OH production,as opposed to symmetric O-Cu-O sites that mainly generate HCOOH.This work offers an effective strategy for designing multi-active-site catalysts toward highly selective CO_(2) reduction to C_(2)H_(5)OH and provides fundamental insight into the reaction mechanism.展开更多
基金supported by the Natural Science Foundation of Shandong Province(Nos.ZR2024QE450,ZR2024QB302 and ZR2024QB004)the Taishan Scholars and Young Experts Program of Shandong Province(No.tsqn202211249)Research Program of Qilu Institute of Technology(Nos.QIT 23TP019,QIT23TP010 and QIT24NN007)。
文摘The large volume expansion and rapid capacity attenuation of tin-based electrodes are the main factors limiting their commercial application.The reasonable design of electrode material structure is particularly important for improving its electrochemical performance.Herein,phosphorus-modified graphene encapsulated Sn_(6)O_(4)(OH)_(4)nanoparticles composite(P-Sn_(6)O_(4)(OH)_(4)@RGO)with crystalline-amorphous heterostructure has been successfully designed and prepared.The design of crystalline-amorphous structure has largely enhanced the active sites,and the construction of a graphene encapsulation structure has greatly alleviated volume expansion.Notably,P-Sn_(6)O_(4)(OH)_(4)@RGO obtained an excellent high-rate longterm cycling performance for lithium-ion batteries anode,reaching a high specific capacity of 970 m Ah/g at 1.0 A/g after 1450 cycles.This work demonstrates that restructuring the electrode material's structure and phase through phosphorus modification can effectively improve the electrochemical performance of tin-based electrode materials.
基金financial supports of the National Natural Science Foundation of China (NSFC,Nos.52394202,52476056,and 52301232)the Natural Science Foundation of Chongqing Province (No.2024NSCQ-MSX1109)。
文摘Developing advanced electrocatalysts to convert CO_(2) into liquid fuels such as C_(2)H_(5)OH is critical for utilizing intermittent renewable energy.The formation of C_(2)H_(5)OH,however,is generally less favored compared with the other hydrocarbon products from Cu-based electrocatalysts.In this work,an alkanethiolmodified Cu_(2)O nanowire array(OTT-Cu_(2)O) was constructed with asymmetric Cu sites consisting of paired Cu-O and Cu-S motifs to overcome previous limitations of C_(2)H_(5)OH electrosynthesis via CO_(2)RR pathway.This catalyst achieves a high Faradaic efficiency of 45 % for CO_(2)-to-C_(2)H_(5)OH conversion at 300 m A/cm^(2),representing a more than two-fold enhancement over the Cu_(2)O electrode.Mechanistic investigations reveal that the Cu-S site exhibits distinct C-binding capability that stabilizes key intermediates(^(*)OCH_(2) and ^(*)CO),in contrast to the O-affinitive Cu-O site.The asymmetric S-Cu-O configuration promotes thermodynamically favorable asymmetric C-C coupling between ^(*)CO and ^(*)OCH_(2),forming the critical CO-OCH_(2) intermediate and facilitating C_(2)H_(5)OH production,as opposed to symmetric O-Cu-O sites that mainly generate HCOOH.This work offers an effective strategy for designing multi-active-site catalysts toward highly selective CO_(2) reduction to C_(2)H_(5)OH and provides fundamental insight into the reaction mechanism.
