CO₂‐Mediated Hydrogen Energy Release‐Storage Enabled by Arc‐Discharge‐Synthesized High‐Dispersion Platinum Catalysts

Abstract

Developing and fabricating a heterogeneous material for efficient dehydrogenation of formic acid (FA) to H2 coupled with hydrogenation of CO2 back to FA is a promising strategy to forming a carbon‐neutral CO2‐mediated hydrogen energy release‐storage system, which remains challenging. Herein, a facile one‐step ultrahigh‐temperature method of arc‐discharge route for synthesizing efficient single‐crystal α‐MoC supported platinum catalysts with high dispersion of Pt single atoms (SAs), nanoclusters (NCs), and nanoparticles (NPs) is reported. These catalysts exhibit remarkable performance for the adsorption properties and chemical conversion of small molecules including room‐temperature FA dehydrogenation, CO2 hydrogenation to FA (formate), and low‐temperature CO oxidation reactions. The enhanced electron transfer from MoC to active Pt species improves catalyst's surface electron density, thus modulating the chemical adsorption of these small molecules. The engineered 0.1Pt/MoC with Pt SAs shows an outstanding FA dehydrogenation efficiency, with ca. 100% FA conversion and an initial TOF of up to 7739 h−1 at 25 °C. The versatile 0.1Pt/MoC also displays the ability for converting CO2 hydrogenation back to the hydrogen storage carrier FA (formate) with 88.3% yield under mild conditions. Moreover, in‐depth insights into the material microstructure, Pt−MoC electronic interactions, reaction‐dependent particle size effect, and adsorption energy are comprehensively investigated.