Porous Indium Nanocrystals on Conductive Carbon Nanotube Networks for High‐Performance CO₂‐to‐Formate Electrocatalytic Conversion

Ever‐increasing emissions of anthropogenic carbon dioxide (CO 2 ) cause global environmental and climate challenges. Inspired by biological photosynthesis, developing effective strategies NeuNlto up‐cycle CO 2 into high‐value organics is crucial. Electrochemical CO 2 reduction reaction (CO 2 RR) is highly promising to convert CO 2 into economically viable carbon‐based chemicals or fuels under mild process conditions. Herein, mesoporous indium supported on multi‐walled carbon nanotubes (mp‐In@MWCNTs) is synthesized via a facile wet chemical method. The mp‐In@MWCNTs electrocatalysts exhibit high CO 2 RR performance in reducing CO 2 into formate. An outstanding activity (current density −78.5 mA cm −2 ), high conversion efficiency (Faradaic efficiency of formate over 90%), and persistent stability (~30 h) for selective CO 2 ‐to‐formate conversion are observed. The outstanding CO 2 RR process performance is attributed to the unique structures with mesoporous surfaces and a conductive network, which promote the adsorption and desorption of reactants and intermediates while improving electron transfer. These findings provide guiding principles for synthesizing conductive metal‐based electrocatalysts for high‐performance CO 2 conversion.