Platinum nanoparticles supported on dendritic mesoporous silica nanoparticles with tunable size as ethylene scavengers for food preservation

Platinum-loaded dendritic mesoporous silica catalysts (Pt/DMS) with the size controlled by changing the molar ratio of NaSal/CTAB (φ) were successfully prepared using an incipient impregnating method. The resulting catalysts with high specific surface areas and distinctive central-radial pore channels exhibited excellent ethylene catalytic oxidation at low temperatures, enabling the complete ethylene conversion at 25 °C for 60 h and even at 0 °C for 200 min. The φ value plays an important role in controlling the DMS support structure and Pt activity. The high efficiency of low-temperature ethylene oxidation and long-term stability for Pt/DMS are attributed to high Pt dispersion, small Pt size, high Pt 0 content and the rapid CO oxidation process. As an ethylene scavenger, Pt/DMS delayed the postharvest decay, deterioration, and storage quality loss of bananas and avocados, demonstrating the significant potential of as-prepared catalysts in the applications associated with fruit and vegetable (F&V) preservation.