Rational design of Pt-integrated SnNbO/BiMoO monolayer S-scheme heterojunction for efficient ethylene removal toward fresh produce preservation.

Effective removal of ethylene (CH) during fruit and vegetables storage and transport remains a critical challenge for post-harvest preservation. Although S-scheme heterojunctions can improve charge separation and redox capacity for ethylene degradation, their efficiency is still restricted by limited carrier transfer and sluggish oxygen activation. Here, we rationally designed a novel 2D/2D SnNbO/BiMoO monolayer S-scheme heterojunction integrated with Pt co-catalyst to address these limitations. Density Functional Theory (DFT) calculations revealed the S-scheme charge transfer pathway, which was experimentally realized via electrostatic self-assembly followed by annealing-induced atomic interface bonding. Photodeposited Pt nanoparticles further promoted O activation at reduction sites. The optimized Pt-50-SNOBMO achieved an outstanding visible-light-driven degradation rate (139.2 × 10 min), 248.6 and 143.5 times higher than pristine SnNbO and BiMoO, representing the best performance reported to date for ethylene removal. Extensive spectroscopic and microscopic analyses confirmed the robust interface interactions and S-scheme mechanism. This study provides new insights into heterojunction engineering and offers a promising strategy for advanced photocatalytic preservation technologies.