Photoactive Tungsten-Oxide Nanomaterials for Water-Splitting

• Published in: Nanomaterials (Basel, Switzerland) Switzerland), 2020-09, Vol.10 (9), p.1871
• Main Authors: Shabdan, Yerkin, Markhabayeva, Aiymkul, Bakranov, Nurlan, Nuraje, Nurxat
• Format: Article
• Language: English
• Subjects: Alternative energy sources; Charge transfer; Current carriers; Decomposition; Diffusion length; Efficiency; Electrolytes; Electron mobility; Fossil fuels; Fuel cells; Gases; heterostructures; Hydrogen; Light; Liquid-solid interfaces; Morphology; Nanocomposites; Nanomaterials; Nanotechnology; Oxidation; oxygen evolution; Photocatalysis; Photocatalysts; Photoelectrochemical devices; Physical chemistry; Recombination; Renewable resources; Review; Reviews; Semiconductors; Solar energy; Tungsten; Tungsten oxide; Tungsten oxides; Water splitting; WO3
• ISSN: 2079-4991; 2079-4991
• DOI: 10.3390/nano10091871

This review focuses on tungsten oxide (WO ) and its nanocomposites as photoactive nanomaterials for photoelectrochemical cell (PEC) applications since it possesses exceptional properties such as photostability, high electron mobility (~12 cm V s ) and a long hole-diffusion length (~150 nm). Although WO has demonstrated oxygen-evolution capability in PEC, further increase of its PEC efficiency is limited by high recombination rate of photogenerated electron/hole carriers and slow charge transfer at the liquid-solid interface. To further increase the PEC efficiency of the WO photocatalyst, designing WO nanocomposites via surface-interface engineering and doping would be a great strategy to enhance the PEC performance via improving charge separation. This review starts with the basic principle of water-splitting and physical chemistry properties of WO , that extends to various strategies to produce binary/ternary nanocomposites for PEC, particulate photocatalysts, Z-schemes and tandem-cell applications. The effect of PEC crystalline structure and nanomorphologies on efficiency are included. For both binary and ternary WO nanocomposite systems, the PEC performance under different conditions-including synthesis approaches, various electrolytes, morphologies and applied bias-are summarized. At the end of the review, a conclusion and outlook section concluded the WO photocatalyst-based system with an overview of WO and their nanocomposites for photocatalytic applications and provided the readers with potential research directions.