Efficient Light Responsive (UCNPs)-Pt@MOF/Au Composites for Photocatalytic Hydrogen Evolution By Harvesting from Extended UV to Near-Infrared

Photocatalytic water splitting by utilizing broadband spectral response from UV to near-infrared (NIR) region is a big challenge and yet a prime target. 50% of the solar spectrum constituted by NIR light and in this work, our target is to increase absorption range from UV-visible to NIR by using (UCNPs)-Pt@MOF/Au composites. In this context, lanthanide-doped upconversion nanoparticles (UCNPs) are able to convert NIR to UV and visible, which are then harvested by metal-organic framework (MOF) and Au. MOF and plasmonic Au nanoparticles (NPs) broaden the absorption of UV light to a visible region as well as speed up the transfer of charges considerably. For this experiment, we used MIL-125 as a MOF because it is a wide-bandgap semiconductor. The spatial separation of Pt and Au particles by the MOF further steers the charge migration and also provides access to active Pt sites for the catalytic product as a result, the optimized composite exhibits high photocatalytic H2 production rate under UV, visible and NIR regions.