| 초록 |
Among various metal catalysts, Pd is one of the most effective catalysts for the electrochemical reduction of CO2 to formate, a valuable liquid product, at low overpotential. However, Pd metal has intrinsically high CO affinity which makes the metal surface vulnerable to CO poisoning, resulting in rapid deactivation toward CO2 electroreduction. Herein, we design novel catalyst utilizing the interaction between metals and metal−organic frameworks. Atomically dispersed Au on tensile-strained Pd nanoparticles shows significantly improved formate production activity, selectivity, and stability with high CO poisoning tolerance. Moreover, we found that the tensile strain stabilizes all reaction intermediates on the Pd surface, whereas the atomically dispersed Au selectively destabilizes CO* without affecting other adsorbates. As a result, the conventional COOH* versus CO* scaling relation is broken, and our catalyst exhibits 26- and 31-fold enhancement in partial current density and mass activity toward electrocatalytic formate production with over 99% faradaic efficiency, compared to Pd/C at −0.25 V versus RHE. |
