Photoinduced synthesis of ultrafine Pt nanoparticles loaded on the surface of metal-organic frameworks-modified carbon materials for efficient catalytic reduction reactions.

This article focuses on the photoinduced synthesis of ultrafine platinum (Pt) nanoparticles loaded on metal-organic frameworks (MOFs)-modified carbon materials (Co-N-C) and their catalytic performance in the reduction of 4-nitrophenol (4-NP). Using near-ultraviolet (395 nm) and visible light irradiation without additional reducing agents, Pt nanoparticles with average sizes of 2.39 to 3.53 nm were uniformly deposited on Co-N-C carriers derived from carbonized ZIF-8@ZIF-67. The catalyst prepared under 395 nm near-ultraviolet light (Pt/Co-N-C-1) exhibited the highest catalytic activity (rate constant k = 0.64 min⁻¹) and maintained about 90% conversion efficiency after five reuse cycles, demonstrating good stability and reusability. Characterization techniques including X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy confirmed the successful synthesis and dispersion of Pt nanoparticles on the Co-N-C support. This study provides a green, photochemical method for preparing highly active and stable Pt-based catalysts for environmental and energy-related applications.