In Situ Surface‐Enhanced Raman Spectroscopy of CO2 Reduction by Metal‐Organic Framework‐Derived Copper Electrode

By pyrolyzing Cu‐based MOFs, a Cu 0 /Cu +1 /C/N catalyst with a porous carbon layer coating was synthesized. The combination of the Cu ion‐rich active sites derived from MOFs and the Raman signal enhancement associated with Cu nanostructures and charge–transfer interactions, which contributes to the SERS effect, was utilized for in situ investigation of the electrochemical CO 2 reduction reaction (CO 2 RR) process. This study focuses on the catalytic performance and reaction mechanisms of Cu‐MOF‐derived materials in the electrocatalytic CO 2 reduction reaction, using in situ Raman and SERS techniques for real‐time monitoring and characterization. The results indicate that Cu‐MOF‐derived materials significantly enhance the selectivity toward C 2 products by tuning the valence state distribution of copper (Cu(I)/Cu(0)) and the structure of active sites. Moreover, the porous carbon‐coated Cu elements exhibit stable catalytic performance during the electrocatalytic process (inhibiting hydrogen evolution reaction and stabilizing the valence state of Cu ions). In addition, in situ spectroscopy reveals the dynamic evolution of key intermediates (such as *CO and *CHO) and the ion adsorption process on the catalyst surface, providing crucial insights into the catalytic behavior of Cu‐MOF‐derived materials. We synthesized a Cu 0 /Cu + /C/N catalyst with a porous carbon coating by pyrolyzing Cu‐based MOFs. The abundant Cu‐ion active sites inherited from the MOF structure and the electromagnetic‐field–enhanced charge‐transfer effect of the carbon matrix enable strong SERS activity for in situ monitoring of the CO 2 reduction reaction (CO 2 RR). Using in situ Raman and SERS, we investigated the catalytic performance and reaction mechanism of Cu‐MOF‐derived materials. The results show that regulating the Cu 0 /Cu + valence distribution and tuning the active‐site structure significantly enhance C 2 product selectivity. The porous carbon layer further stabilizes Cu species and suppresses the competing hydrogen evolution reaction, ensuring durable catalytic performance. In situ spectroscopy reveals the dynamic evolution of key intermediates (*CO, *CHO) and ion‐adsorption behavior on the catalyst surface, providing critical mechanistic insights. This work highlights the potential of MOF‐derived Cu catalysts for efficient CO 2 RR and offers guidance for designing advanced electrocatalysts.