Confined electrochemical catalysis under cover: Enhanced CO2reduction at the interface between graphdiyne and Cu surface

Two-dimensional (2D) confined catalysis, in which reactions occur in restricted space between metal surface and 2D overlayer, opens up a new thread for enhancement in the performance of common catalysts. In this paper, Cu surface covered with graphdiyne (GDY) is proposed as an excellent catalyst for 2D confined electrochemical CO2 reduction. Density functional theory calculations reveal the superiority of GDY overlayer in reducing the free energies of key intermediates and onset voltage. In the confined space underneath GDY cover, reaction intermediates are stabilized due to charge transfer between adsorbates and GDY. With large holes as molecular tunnels, GDY has an advantage over graphene in 2D confined catalysis. Our findings inspire a new method to enhance the performance of catalysts through coating with porous 2D materials.