RESUMEN
Production of multicarbon (C2+ ) liquid fuels is a challenging task for electrocatalytic CO2 reduction, mainly limited by the stabilization of reaction intermediates and their subsequent C-C couplings. In this work, we report a unique catalyst, the coordinatively unsaturated Cu sites on amorphous CuTi alloy (a-CuTi@Cu) toward electrocatalytic CO2 reduction to multicarbon (C2-4 ) liquid fuels. Remarkably, the electrocatalyst yields ethanol, acetone, and n-butanol as major products with a total C2-4 faradaic efficiency of about 49 % at -0.8â V vs. reversible hydrogen electrode (RHE), which can be maintained for at least 3â months. Theoretical simulations and in situ characterization reveals that subsurface Ti atoms can increase the electron density of surface Cu sites and enhance the adsorption of *CO intermediate, which in turn reduces the energy barriers required for *CO dimerization and trimerization.
RESUMEN
A grand challenge for proton exchange membrane electrolyzers is the rational design of oxygen evolution reaction electrocatalysts to balance activity and stability. Here, we report a support-stabilized catalyst, the activated ~200 nm-depth IrW nanochannel that achieves the current density of 2 A cm-2 at an overpotential of only ~497 mV and maintains ultrastable gas evolution at 100 mA cm-2 at least 800 h with a negligible degradation rate of ~4 µV h-1. Structure analyses combined with theoretical calculations indicate that the IrW support alters the charge distribution of surface (IrO2)n clusters and effectively confines the cluster size within 4 (n≤4). Such support-stabilizing effect prevents the surface Ir from agglomeration and retains a thin layer of electrocatalytically active IrO2 clusters on surface, realizing a win-win strategy for ultrahigh OER activity and stability. This work would open up an opportunity for engineering suitable catalysts for robust proton exchange membrane-based electrolyzers.