Insight into the Transition-Metal Hydroxide Cover Layer for Enhancing Photoelectrochemical Water Oxidation.
Xingming NingPeiyao DuZhengang HanJing ChenXiao-Quan LuPublished in: Angewandte Chemie (International ed. in English) (2020)
Depositing a transition-metal hydroxide (TMH) layer on a photoanode has been demonstrated to enhance photoelectrochemical (PEC) water oxidation. However, the controversial understanding for the improvement origin remains a key challenge to unlock the PEC performance. Herein, by taking BiVO4 /iron-nickel hydroxide (BVO/Fx N4-x -H) as a prototype, we decoupled the PEC process into two processes including charge transfer and surface catalytic reaction. The kinetic information at the BVO/Fx N4-x -H and Fx N4-x -H/electrolyte interfaces was systematically evaluated by employing scanning photoelectrochemical microscopy (SPECM), intensity modulated photocurrent spectroscopy (IMPS) and oxygen evolution reaction (OER) model. It was found that Fx N4-x -H acts as a charge transporter rather than a sole electrocatalyst. PEC performance improvement is mainly ascribed to the efficient suppression of charge recombination by fast hole transfer kinetics at BVO/Fx N4-x -H interface.
Keyphrases
- transition metal
- visible light
- quantum dots
- label free
- reduced graphene oxide
- high resolution
- electron transfer
- sensitive detection
- single molecule
- aqueous solution
- hydrogen peroxide
- solar cells
- dna damage
- gold nanoparticles
- high throughput
- healthcare
- health information
- single cell
- social media
- solid state
- iron deficiency