Zheng Min, Wang Pengtang, Zhi Xing, Yang Kang, Jiao Yan, Duan Jingjing, Zheng Yao, Qiao Shi-Zhang
School of Chemical Engineering and Advanced Materials, The University of Adelaide, Adelaide, SA 5005, Australia.
School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
J Am Chem Soc. 2022 Aug 17;144(32):14936-14944. doi: 10.1021/jacs.2c06820. Epub 2022 Aug 4.
An ampere-level current density of CO electrolysis is critical to realize the industrial production of multicarbon (C) fuels. However, under such a large current density, the poor CO intermediate (*CO) coverage on the catalyst surface induces the competitive hydrogen evolution reaction, which hinders CO reduction reaction (CORR). Herein, we report reliable ampere-level CO-to-C electrolysis by heteroatom engineering on Cu catalysts. The Cu-based compounds with heteroatom (N, P, S, O) are electrochemically reduced to heteroatom-derived Cu with significant structural reconstruction under CORR conditions. It is found that N-engineered Cu (N-Cu) catalyst exhibits the best CO-to-C productivity with a remarkable Faradaic efficiency of 73.7% under -1100 mA cm and an energy efficiency of 37.2% under -900 mA cm. Particularly, it achieves a C partial current density of -909 mA cm at -1.15 V versus reversible hydrogen electrode, which outperforms most reported Cu-based catalysts. spectroscopy indicates that heteroatom engineering adjusts *CO adsorption on Cu surface and alters the local H proton consumption in solution. Density functional theory studies confirm that the high adsorption strength of *CO on N-Cu results from the depressed HER and promoted *CO adsorption on both bridge and atop sites of Cu, which greatly reduces the energy barrier for C-C coupling.
对于实现多碳（C）燃料的工业化生产而言，一氧化碳电解的安培级电流密度至关重要。然而，在如此大的电流密度下，催化剂表面一氧化碳中间体（CO）覆盖率较低会引发竞争性析氢反应，从而阻碍一氧化碳还原反应（CORR）。在此，我们报道了通过对铜催化剂进行杂原子工程实现可靠的安培级一氧化碳到碳的电解。含杂原子（N、P、S、O）的铜基化合物在CORR条件下通过电化学还原为具有显著结构重构的杂原子衍生铜。研究发现，氮工程化铜（N-Cu）催化剂表现出最佳的一氧化碳到碳的生产率，在-1100 mA cm下法拉第效率高达73.7%，在-900 mA cm下能量效率为37.2%。特别地，在相对于可逆氢电极-1.15 V时，其实现了-909 mA cm的碳分电流密度，优于大多数已报道的铜基催化剂。光谱表明，杂原子工程调节了CO在铜表面的吸附，并改变了溶液中局部H质子消耗。密度泛函理论研究证实，CO在N-Cu上的高吸附强度源于析氢反应受到抑制以及CO在铜的桥位和顶位上的吸附增强，这大大降低了碳-碳偶联的能垒。
