清华大学罗雨婷团队报道了通过中间体平衡同时实现，电催化二氧化碳到CH₄的高电流密度和选择性。相关研究成果于2024年12月26日发表于国际顶尖学术期刊《德国应用化学》。

CO₂电化学还原为CH₄对于碳中和和可再生能源储存是有希望的，但面临着低的CH₄选择性，尤其是在高电流密度下。关键的挑战在于促进*CO中间体和*H偶联，同时尽量减少包括C-C偶联或H-H偶联在内的副反应，由于中间体丰富，在高电流密度下尤其困难。

该文中，研究人员报告了一种合作策略，使用包含Cu-N配位聚合物和CuO组分的铜基催化剂来应对这一挑战，该催化剂可以同时管理关键中间体*CO和*H。在1300 mA cm^-2下，CO₂到CH₄的快速转化率为3.14 mmol cm^-2 h^-1，法拉第效率为51.7%。

原位光谱和理论计算表明，Cu-N配位聚合物组分中Cu-Cu距离的增加有利于多步*CO氢化而非二聚，CuO组分确保了*H的充足供应，共同有助于在高电流密度下选择性地将CO₂转化为CH₄。

该研究通过合理的催化剂设计，开发了一种同时具有高电流密度和高选择性的CH₄电合成合作策略，为其应用铺平了道路。

附：英文原文

Title: Simultaneous High Current Density and Selective Electrocatalytic CO2-to-CH4 through Intermediate Balancing

Author: Bilu Liu, Shuqi Hu, Yumo Chen, Zhiyuan Zhang, Heming Liu, Xin Kang, Jiarong Liu, Shanlin Li, Yuting Luo

Issue&Volume: 2024-12-26

Abstract: The electrochemical reduction of CO2 to CH4 is promising for carbon neutrality and renewable energy storage but confronts low CH4 selectivity, especially at high current densities. The key challenge lies in promoting *CO intermediate and *H coupling while minimizing side reactions including C-C coupling or H-H coupling, which is particularly difficult at high current density due to abundant intermediates. Here we report a cooperative strategy to address this challenge using Cu-based catalysts comprising Cu-N coordination polymer and CuO component that can simultaneously manage the key intermediates *CO and *H. A fast CO2-to-CH4 conversion rate of 3.14 mmol cm-2 h-1 is achieved at 1,300 mA cm2 with a Faradaic efficiency of 51.7%. In-situ spectroscopy and theoretical calculations show that the increased Cu-Cu distance in the Cu-N coordination polymer component favors multistep *CO hydrogenation over the dimerization, and the CuO component ensures an adequate supply of *H, together contributing to the selective CO2-to-CH4 conversion at high current densities. This work develops a cooperative strategy for the electrosynthesis of CH4 with simultaneous high current density and high selectivity by rational catalyst design, paving the way for its applications.

DOI: 10.1002/anie.202423915

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202423915