Electrochemical Ultrathin Metal‐Atomic Layer Deposition for Silica Microenvironment‐Assisted Cu‐Based Catalysis

Abstract Replacing commonly used precious and rare noble metals by the abundant copper (Cu)‐based catalysts is highly desired for sustainable fine‐chemical synthesis. However, in the lack of model platforms, complex surface chemistry of randomly nanostructured bulk Cu is notoriously challenging to understand and control. By synthesizing ultrathin 2D‐Cu layer sandwiched inside the bilayer silica template, an unusual but critical cooperative role of Lewis basic amino‐silica microenvironment for [Cu]‐catalyzed selective hydrogenation of unsaturated C─C bonds in diverse alkynes, ene‐ynes, and α,β‐unsaturated (alkene) Michael acceptors is discovered. Newly developed nanospace‐confined electrochemical (eChem) atomic layer deposition (NC‐EAD) technique afforded < 2 nm ultrathin Cu(0)‐layer intimately covered inside silica envelope. This model platform aided the detailed mechanistic study deciphering the unexpected finding – originally non‐reactive Cu‐film, just by a simple silica coating step, turning into an efficient catalyst for scalable fine‐chemical synthesis. The concept of reactive metal surface‐microenvironment manipulation, presents a new paradigm for controlling complex molecular interactions in heterogeneous catalysts.