Highly Selective Tandem Electroreduction of CO to Ethylene over Atomically Isolated Nickel-Nitrogen Site/Copper Nanoparticle Catalysts.

Herein, an effective tandem catalysis strategy is developed to improve the selectivity of the CO RR towards C H by multiple distinct catalytic sites in local vicinity. An earth-abundant elements-based tandem electrocatalyst PTF(Ni)/Cu is constructed by uniformly dispersing Cu nanoparticles (NPs) on the porphyrinic triazine framework anchored with atomically isolated nickel-nitrogen sites (PTF(Ni)) for the enhanced CO RR to produce C H . The Faradaic efficiency of C H reaches 57.3 % at -1.1 V versus the reversible hydrogen electrode (RHE), which is about 6 times higher than the non-tandem catalyst PTF/Cu, which produces CH as the major carbon product. The operando infrared spectroscopy and theoretic density functional theory (DFT) calculations reveal that the local high concentration of CO generated by PTF(Ni) sites can facilitate the C-C coupling to form C H on the nearby Cu NP sites. The work offers an effective avenue to design electrocatalysts for the highly selective CO RR to produce multicarbon products via a tandem route.