Phase-engineered 1T/2H MoS2 heterophase junctions boost low-temperature pathway-selective CO2 hydrogenation to methanol

Heterophase junction engineering enables intrinsic promotion without additives. • Electron-rich S v obtained via 1T → 2H charge transfer boosts intrinsic activity. • Heterophase junctions redistribute network with formate pathway promoted. Thermocatalytic hydrogenation of CO 2 to methanol offers a promising route for carbon recycling and renewable energy storage, yet achieving high activity and methanol selectivity under low-temperature conditions remains challenging. Herein, we construct MoS 2 catalysts with tunable 1T/2H phase ratios by phase engineering, enabling the formation of well-defined heterophase junctions. Through interfacial charge transfer, metallic 1T domains serve as intrinsic electron donors to sulfur vacancies on adjacent 2H domains, thereby modulating their electronic structure. This heterophase-junction-mediated electronic regulation enhances the intrinsic catalytic activity while steering methanol synthesis toward the formate-mediated pathway. Consequently, the optimized 1T/2H-700 catalyst containing 4.7% 1T phase exhibits approximately 1.6-fold intrinsic activity compared with the pure 2H phase catalyst, achieving an impressive 6.3% CO 2 conversion and 87.1% methanol selectivity at the low temperature of 200 °C. More importantly, this work establishes heterophase junction engineering as an intrinsic-promoter strategy for electronic regulation of catalytic sites, providing a new catalyst design principle beyond conventional promoter-assisted systems. Download: Download high-res image (138KB) Download: Download full-size image