Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)acc...Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic performances.The CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution reaction.With the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO intermediates.Additionally,we find extra CO production is indispensable for the robust production of C2H4.An inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable electrolysis.Guided by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing C2H4.Our work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes.展开更多
Metal-free electrocatalysts for the oxygen evolution reaction(OER)are gaining attention for their low cost,high conductivity,and moderate catalytic performance.While trace metal interference in assynthesized catalysts...Metal-free electrocatalysts for the oxygen evolution reaction(OER)are gaining attention for their low cost,high conductivity,and moderate catalytic performance.While trace metal interference in assynthesized catalysts has been ruled out,the impact of trace metal contamination during electrochemical activation remains unexplored.This study demonstrates that anodic pretreatment in alkaline electrolytes enhances the catalytic performance of carbon cloth.Specifically,carbon cloth activated in 8 mol/L Na OH achieves a current density of 10 m A/cm^(2)with an overpotential of only 338 m V,comparable to metalbased OER catalysts.Electrochemical and spectroscopic analyses show the deposition of Fe Ni O_(x)H_(y)oxyhydroxides(0.19±0.06μg/cm^(2))on specific sites of the carbon substrate during activation.These nanoparticles contribute significantly to the catalytic activity,with a synergistic effect between Fe Ni O_(x)H_(y)and the carbon substrate.The turnover frequency(TOF)for Fe correlates with the amount of C=O groups on the carbon substrate,providing evidence for an interfacial synergistic effect.This work emphasizes the importance of considering trace metal effects in metal-free catalyst evaluation and offers insights for the design of more efficient carbon-based hybrid OER catalysts.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.22479097)the Shanghai Science and Technology Committee(Grant No.23ZR1433000)the National High-Level Talent Program for Young Scholars,the Start-up Fund(F.S.)from Shanghai Jiao Tong University.
文摘Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially understood.Here,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic performances.The CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution reaction.With the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO intermediates.Additionally,we find extra CO production is indispensable for the robust production of C2H4.An inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable electrolysis.Guided by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing C2H4.Our work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes.
基金financially supported by the National Natural Science Foundation of China(No.22479097)the Shanghai Science and Technology Committee(Nos.23ZR1433000 and 22511100400)+1 种基金the National High-Level Talent Program for Young Scholarsthe Start-up Fund(F.Song)from Shanghai Jiao Tong University。
文摘Metal-free electrocatalysts for the oxygen evolution reaction(OER)are gaining attention for their low cost,high conductivity,and moderate catalytic performance.While trace metal interference in assynthesized catalysts has been ruled out,the impact of trace metal contamination during electrochemical activation remains unexplored.This study demonstrates that anodic pretreatment in alkaline electrolytes enhances the catalytic performance of carbon cloth.Specifically,carbon cloth activated in 8 mol/L Na OH achieves a current density of 10 m A/cm^(2)with an overpotential of only 338 m V,comparable to metalbased OER catalysts.Electrochemical and spectroscopic analyses show the deposition of Fe Ni O_(x)H_(y)oxyhydroxides(0.19±0.06μg/cm^(2))on specific sites of the carbon substrate during activation.These nanoparticles contribute significantly to the catalytic activity,with a synergistic effect between Fe Ni O_(x)H_(y)and the carbon substrate.The turnover frequency(TOF)for Fe correlates with the amount of C=O groups on the carbon substrate,providing evidence for an interfacial synergistic effect.This work emphasizes the importance of considering trace metal effects in metal-free catalyst evaluation and offers insights for the design of more efficient carbon-based hybrid OER catalysts.
