Electrocatalytic CO_(2) reduction(CO_(2) RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C_(2+)generation due to th...Electrocatalytic CO_(2) reduction(CO_(2) RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C_(2+)generation due to their unique C–C coupling activity,yet the in situ reduction from Cu^(+) to Cu^(0) under cathodic potentials causes the catalyst deactivation.Herein,we develop a transient thermal shock strategy to embed Cu^(+) species into CeO_(2) lattices,constructing a CuO_(x)/CuCeO_(x)catalyst with a radial gradient Cu^(+) -Ov-Ce^(3+)/Ce^(4+)structure.Depth-profiling X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations reveal that mismatched metal/oxygen diffusion kinetics drive continuous electron transfer from surface Cu^(+) to bulk Ce^(3+)/Ce^(4+)via oxygen vacancies(Ov),forming a dynamic“self-sacrificial”structure to preserve surface Cu^(+) states.In CO_(2)-saturated 0.1 M KHCO_(3),the optimized CuO_(x)/CuCeO_(x)-10 achieves a high C_(2) Faradaic efficiency(FE)of 85.8%at-1.4 V vs.RHE.In situ attenuated total reflection surface-enhanced infrared adsorption spectroscopy(ATR-SEIRAS)identifies the key intermediates of C_(2) are*OCCO and*OCCOH,while DFT reveals a drastic reduction of C–C coupling barrier from 0.842 to0.274 eV.This work demonstrates kinetically tailored metal-support interactions,enabling oxidationstate control for pathway-selective catalysis.展开更多
二氧化碳电还原有利于二氧化碳高价值利用和间歇性电能的存储,是一种极具应用前景的新技术.自支撑催化剂比粉末催化剂在构建电极方面具有明显优势,但缺乏有效的合成方法.本研究采用电纺丝-碳化法合成了一种自支撑的BiCu/碳杂化纳米纤维...二氧化碳电还原有利于二氧化碳高价值利用和间歇性电能的存储,是一种极具应用前景的新技术.自支撑催化剂比粉末催化剂在构建电极方面具有明显优势,但缺乏有效的合成方法.本研究采用电纺丝-碳化法合成了一种自支撑的BiCu/碳杂化纳米纤维膜(BiCu/CHNM),可直接用作工作电极在流动池中将二氧化碳还原为甲酸盐,其法拉第效率为87.67%,分电流密度为142.9 mA cm^(-2).稳定性测试中,甲酸盐的法拉第效率在高偏电流密度(>100 mA cm^(-2))下可在50小时内连续保持在80%以上.原位拉曼光谱和密度泛函理论计算证实,铜掺杂降低了Bi(012)平面上HCOO~-形成的能垒,同时提高了碳纳米纤维网络的导电性.由于同时具有高导电框架结构和高度分散的BiCu活性位点,这种杂化膜同时表现出高活性、高选择性和长时间稳定性.展开更多
基金financially supported by the National Natural Science Foundation of China(22378428,22138013)the National Key Research and Development Program of China(2023YFB4104500,2023YFB4104503)+1 种基金the Key Research and Development Program of Shandong Province(2024ZLGX08)the Science and Technology Innovation Project of the Shandong Energy Group Co.,Ltd.(SNKJ2023A03)。
文摘Electrocatalytic CO_(2) reduction(CO_(2) RR)toward multi-carbon compounds is a challenging but meaningful route for carbon cycling.Copper-based catalysts are the most promising candidate for C_(2+)generation due to their unique C–C coupling activity,yet the in situ reduction from Cu^(+) to Cu^(0) under cathodic potentials causes the catalyst deactivation.Herein,we develop a transient thermal shock strategy to embed Cu^(+) species into CeO_(2) lattices,constructing a CuO_(x)/CuCeO_(x)catalyst with a radial gradient Cu^(+) -Ov-Ce^(3+)/Ce^(4+)structure.Depth-profiling X-ray photoelectron spectroscopy(XPS)and density functional theory(DFT)calculations reveal that mismatched metal/oxygen diffusion kinetics drive continuous electron transfer from surface Cu^(+) to bulk Ce^(3+)/Ce^(4+)via oxygen vacancies(Ov),forming a dynamic“self-sacrificial”structure to preserve surface Cu^(+) states.In CO_(2)-saturated 0.1 M KHCO_(3),the optimized CuO_(x)/CuCeO_(x)-10 achieves a high C_(2) Faradaic efficiency(FE)of 85.8%at-1.4 V vs.RHE.In situ attenuated total reflection surface-enhanced infrared adsorption spectroscopy(ATR-SEIRAS)identifies the key intermediates of C_(2) are*OCCO and*OCCOH,while DFT reveals a drastic reduction of C–C coupling barrier from 0.842 to0.274 eV.This work demonstrates kinetically tailored metal-support interactions,enabling oxidationstate control for pathway-selective catalysis.
基金supported by the National Natural Science Foundation of China (52072409)the Major Scientific and Technological Innovation Project of Shandong Province (2020CXGC010403)Taishan Scholar Project of Shandong Province of China (ts201712020)。
文摘二氧化碳电还原有利于二氧化碳高价值利用和间歇性电能的存储,是一种极具应用前景的新技术.自支撑催化剂比粉末催化剂在构建电极方面具有明显优势,但缺乏有效的合成方法.本研究采用电纺丝-碳化法合成了一种自支撑的BiCu/碳杂化纳米纤维膜(BiCu/CHNM),可直接用作工作电极在流动池中将二氧化碳还原为甲酸盐,其法拉第效率为87.67%,分电流密度为142.9 mA cm^(-2).稳定性测试中,甲酸盐的法拉第效率在高偏电流密度(>100 mA cm^(-2))下可在50小时内连续保持在80%以上.原位拉曼光谱和密度泛函理论计算证实,铜掺杂降低了Bi(012)平面上HCOO~-形成的能垒,同时提高了碳纳米纤维网络的导电性.由于同时具有高导电框架结构和高度分散的BiCu活性位点,这种杂化膜同时表现出高活性、高选择性和长时间稳定性.
