Abstract：
Electrochemical CO2 reduction reaction (eCO2RR) over Cu-based catalysts is a promising approach for efficiently converting CO2 into value-added chemicals and alternative fuels. However, achieving controllable product selectivity from eCO2RR remains challenging because of the difficulty in controlling the oxidation states of Cu against robust structural reconstructions during the eCO2RR. Herein, we report a novel strategy for tuning the oxidation states of Cu species and achieving eCO2RR product selectivity by adjusting the Cu content in CuMgAl-layered double hydroxide (LDH)-based catalysts. In this strategy, the highly stable Cu2+ species in low-Cu-containing LDHs facilitated the strong adsorption of *CO intermediates and further hydrogenation into CH4. Conversely, the mixed Cu0/Cu+ species in high-Cu-containing LDHs derived from the electroreduction during the eCO2RR accelerated C-C coupling reactions. This strategy to regulate Cu oxidation states using LDH nanostructures with low and high Cu molar ratios produced an excellent eCO2RR performance for CH4 and C2+ products, respectively.
摘要：
Cu基催化剂上的电化学CO2还原反应（eCO2RR）是一种有效地将CO2转化为增值化学品和替代燃料的有前途的方法。然而,从eCO2RR实现可控的产物选择性仍然具有挑战性,因为在eCO2RR期间难以控制Cu的氧化态对抗稳健的结构重建。在这里，我们报告了一种通过调节CuMgAl层状双氢氧化物（LDH）基催化剂中的Cu含量来调节Cu物种的氧化态并实现eCO2RR产物选择性的新策略。在这个战略中,低含Cu的LDH中的高度稳定的Cu2物种促进了*CO中间体的强烈吸附，并进一步氢化为CH4。相反，在eCO2RR加速C-C偶联反应过程中，电还原产生的高含CuLDH中的混合Cu0/Cu物种。使用具有低和高Cu摩尔比的LDH纳米结构来调节Cu氧化态的策略对CH4和C2产物产生了优异的eCO2RR性能。分别。
