西安交通大学沈少华团队报道了聚丙烯酸酯修饰铜电极选择性电化学CO2还原制备多碳产物。相关研究成果发表在2024年6月15日出版的《科学通报》。

在多晶铜（Cu）上通过电化学CO₂还原反应（eCO₂RR）高选择性地生产增值多碳（C₂₊）产品仍然具有挑战性。

该文提出了使用聚（α-氰基丙烯酸乙酯）（PECA）进行简单的表面改性，以大大提高与多晶Cu相上eCO₂RR制备C₂₊的选择性，在1.1Vvs.RHE下，对C₂₊产物的法拉第效率（FE）从Cu电极的30.1%增加到所获得的Cu PECA电极的72.6%。给定对C₂₊产物的确定良好的FEs，在自制的流动池中，在0.9V vs.RHE下，对于Cu PECA电极，C₂₊产生的部分电流密度可以估计为145.4mAcm^-2。

原位光谱表征和理论计算表明，在界面电子密度重新分布和Cu活性位点d带中心（Ed）能级提高的情况下，修饰在Cu电极上的具有受电子 -C≡N和-COOR基团的PECA可以抑制*H中间体的吸附，稳定*CO中间体，从而促进C-C偶联，进而促进C₂₊的选择性产生。

该项研究被认为可以指导用聚合物对电催化剂和电极进行改性，以控制反应中间体的表面吸附行为，从而实现实用的eCO₂RR，制备高活性和选择性的增值C₂₊产物。

附：英文原文

Title: Polyacrylate modified Cu electrode for selective electrochemical CO2 reduction towards multicarbon products

Author: Shaohua Shen a

Issue&Volume: 2024/06/15

Abstract: Highly selective production of value-added multicarbon (C2+) products via electrochemical CO2 reduction reaction (eCO2RR) on polycrystalline copper (Cu) remains challenging. Herein, the facile surface modification using poly (α-ethyl cyanoacrylate) (PECA) is presented to greatly enhance the C2+ selectivity for eCO2RR over polycrystalline Cu, with Faradaic efficiency (FE) towards C2+ products increased from 30.1% for the Cu electrode to 72.6% for the obtained Cu-PECA electrode at 1.1 V vs. reversible hydrogen electrode (RHE). Given the well-determined FEs towards C2+ products, the partial current densities for C2+ production could be estimated to be 145.4 mA cm2 for the Cu-PECA electrode at 0.9 V vs. RHE in a homemade flow cell. In-situ spectral characterizations and theoretical calculations reveal that PECA featured with electron-accepting -C≡N and -COOR groups decorated onto the Cu electrode could inhibit the adsorption of *H intermediates and stabilize the *CO intermediates, given the redistributed interfacial electron density and the raised energy level of d-band center (Ed) of Cu active sites, thus facilitating the C-C coupling and then the C2+ selective production. This study is believed to be guidable to the modification of electrocatalysts and electrodes with polymers to steer the surface adsorption behaviors of reaction intermediates to realize practical eCO2RR towards value-added C2+ products with high activity and selectivity.

DOI: 10.1016/j.scib.2024.06.014

Source: https://www.sciencedirect.com/science/article/abs/pii/S2095927324004250