| 초록 |
Hydrogen is an energy-rich and clean fuel with enormous potential. Utilizing the most abundant resources like water, and solar power, photoelectrochemical (PEC) water splitting enables us to produce hydrogen. Bismuth vanadate (BiVO4) is a potential photoanode candidate in the recent decade due to its favorable outstanding features like moderate bandgap, visible light activity, better chemical stability, and cost-effective synthesis methods. Despite a suitable bandgap of BiVO4 for visible light absorption, most of the photogenerated holes in BiVO4 photoanodes are vanished before reaching the surfaces for oxygen evolution reaction due to the poor charge separation efficiency in the bulk. This work demonstrates a simple thermal treatment approach to generate oxygen vacancies for the design of efficient planar photoanodes for solar hydrogen production. From X-ray diffraction study, formation of monoclinic phase of BiVO4 after annealing at 450 0C has been confirmed. The FE-SEM micrograph reveals the formation of the dense closed pack BiVO4 grains on the substrate surface. EDAX result verify the BiVO4 composition with the presence of stoichiometric Bi, V and O contents. The optical band gap values about 2.4 eV reveals the absorption of broader visible light. Also, the PEC performance and charge transport properties have been explained in detail. |
