Asymmetric Ti-O-Cu bridge synergized with amorphous MXene to boost glycerol oxidation and hydrogen evolution

Size-controllable Cu 2 O nanocubes grow in-situ on AMXene via Oswald-ripening mechanism. • Cu 2 O induces MXene amorphization, generating edge-ligand unsaturated sites for HER. • The electron-rich Cu + boosts orbital hybridization for selective glycerol oxidation. • The catalyst requires only 1.31 V electrolyzer voltage with stability exceeding 150 h. Glycerol oxidation reaction (GOR) is a mild, sustainable pathway with great potential for producing high-value chemicals such as formic acid (FA). Integrating GOR with hydrogen evolution reaction (HER) circumvents the high energy barrier of anodic oxygen evolution in traditional water splitting. However, achieving selective C C bond cleavage in glycerol-to-FA conversion remains a major technical and scientific challenge. Here, via the Ostwald ripening mechanism, size-tunable cuprous oxide nanocubes are in-situ grown on amorphous MXene (Cu 2 O/AMXene), creating well-defined dual active sites with clear functional division: electron-rich Cu + for GOR and Ti sites for HER. The optimized Cu 2 O-0/AMXene (28 nm Cu 2 O) delivers a HER overpotential of 32 mV at 10 mA cm −2 , a GOR potential of 1.13 V at 10 mA cm −2 , and a full electrolyzer voltage of 1.31 V, while maintaining excellent catalytic efficiency after 150 h of continuous operation. Cu 2 O growth induces MXene amorphization, generating edge ligand-unsaturated Ti sites that enhance water dissociation for proton supply, while Ti 4+ promotes hydrogen spillover to transfer protons to Ti 3+ for efficient HER. Electron-rich Cu + forms asymmetric Ti-O-Cu interactions via electron donation from AMXene, enhancing orbital overlap with p orbitals of glycerol oxygen atoms for GOR. This electron-rich environment inhibits Cu + oxidation to Cu 2+ at high anodic potentials, stabilizing the active s - p hybrid configuration. This work also highlights the critical role of O-functional groups on AMXene and lattice O atoms in Cu 2 O for strengthening metal-support interactions. Download: Download high-res image (225KB) Download: Download full-size image