Styrene epoxidation is a key chemical process widely used in the production of polymer intermediates, fine chemicals, and pharmaceuticals. However, traditional methods often rely on hazardous oxidants and show limited efficiency. In a new study published in SCIENCE CHINA Chemistry , a research team led by Prof. Yuchao Zhang from the Institute of Chemistry, Chinese Academy of Sciences, developed a novel photoelectrocatalytic platform that leverages sunlight and the plasmonic effect of gold to drive the reaction in a more sustainable and efficient way.
The platform consists of a gold nanoparticle-modified NiCo 2 O 4 (Au/NiCo 2 O 4 ) photoanode. The gold nanoparticles absorb sunlight and convert it into heat through the localized surface plasmon resonance (LSPR) effect, while the NiCo 2 O 4 nanoneedles enhance catalytic activity and support efficient photothermal conversion. When combined, this system enables the conversion of styrene to epoxide with 94% conversion, 98% selectivity, and 96% Faradaic efficiency.
Mechanistic studies revealed that the photothermal effect plays a crucial role in the reaction: the photoanode surface rapidly heats up under illumination, accelerating bromide oxidation and the generation of bromine radicals, which mediate the epoxidation process. Isotope labeling experiments confirmed water as the sole oxygen source, and scanning electrochemical microscopy (SECM) and infrared thermography validated that local temperature rise promoted mass transport and boosted reaction kinetics.
The catalyst also demonstrated remarkable stability over 100 hours of continuous operation, with negligible structural degradation or performance loss.
This study not only showcases the power of coupling plasmonic heating with photoelectrochemical catalysis but also provides a new direction for designing green and efficient solar-driven chemical transformations.
Science China Chemistry
Experimental study