Sustainable and green synthesis of hydrogen tungsten bronze nanoparticles with nanocarbon via mechanically induced hydrogen spillover

In this study, we demonstrate sustainable and green nanotechnology for room-temperature synthesis of H${}_x$WO${}_3$ ($0<x<0.5$) via a novel reaction pathway induced by mechanical energy. A simple mixture of monoclinic WO${}_3$ powder and polyolefin (polypropylene) is used to obtain H${}_x$WO${}_3$ nanoparticles that show high crystallinity even through high-energy ball milling synthesis. The composite of H${}_x$WO${}_3$ nanoparticles and nanocarbon by-products exhibit unique optoelectronic properties along with outstanding enhancement of photocatalytic performance in the decomposition of azo-dye water pollutants under visible light. The formation mechanism of the obtained functional material is also discussed. The findings of this study provide insights into the limitations for mass production of H${}_x$WO${}_3$ nanoparticles, such as a specific setup for electrochemical reactions and precious metal catalysis.