This review focuses on introducing and explaining electrodepostion mechanisms and electrodeposition-based synthesis strategies used for the production of catalysts and semiconductor electrodes for use in water-splitting photoelectrochemical cells (PECs). It is composed of three main sections: electrochemical synthesis of hydrogen evolution catalysts, oxygen evolution catalysts, and semiconductor electrodes. The semiconductor section is divided into two parts: photoanodes and photocathodes. Photoanodes include n-type semiconductor electrodes that can perform water oxidation to O2 using photogenerated holes, while photocathodes include p-type semiconductor electrodes that can reduce water to H2 using photoexcited electrons. For each material type, deposition mechanisms were reviewed first followed by a brief discussion on its properties relevant to electrochemical and photoelectrochemical water splitting. Electrodeposition or electrochemical synthesis is an ideal method to produce individual components and ...

Electrochemical Synthesis of Photoelectrodes and Catalysts for Use in Solar Water Splitting

Tungsten-based nanomaterials (WO3 & Bi2WO6): Modifications related to charge carrier transfer mechanisms and photocatalytic applications

Label-free photoelectrochemical immunoassay for CEA detection based on CdS sensitized WO3@BiOI heterostructure nanocomposite.

We present a novel all oxides semiconductor WO 3 /Cu 2 O heterojunction photoelectrode applied in photoelectrochemical water splitting. Different amount of Cu 2 O was loaded onto WO 3 NRs by controlling the electrodeposition time and the amount influence on the photoelectrocatalytic activity of the different samples has been researched. This all oxides structure exhibits a remarkably high photoelectrocatalytic performance with a significant improved photocurrent density of 1.37 mA cm −2 was measured at a bias voltage of 0.8 V vs RHE, which was about 3.51 times higher than that of pristine WO 3 NRs. This amazing PEC performance due to the broader light absorption spectrum, the enhanced photogenerated charge carriers transfer efficiency and the suppressive electron-hole recombination rate. The research results can demonstrate a promising way for designing all oxide semiconductor heterojunction structure so that it can improve photoelectrocatalytic efficiency. Moreover, these results also suggest that the WO 3 NRs/Cu 2 O arrays heterojunction structure has a great potential application for efficient PEC water splitting devices.

Highly efficient photocatalyst based on all oxides WO3/Cu2O heterojunction for photoelectrochemical water splitting

As an energy carrier, hydrogen has been extensively studied to satisfy the increasing demand on green energy. Efficiently producing hydrogen from water under sunlight is one of the challenging and important topics in hydrogen energy technology. Photocatalyst plays a critical role for the photo-production of hydrogen from water. It is essential to design novel photocatalysts with enhanced efficiency for the increasing demand on energy. In this paper, recent development on novel strategies to design photocatalysts and novel nanomaterials for efficient production of hydrogen is comprehensively reviewed based on fundamental principles. The strategies, including codoping, hydrogenation, defect engineering, sensitization, formation of heterojunction, metal decoration, band-edge-states modification, and novel designs of cell structures (tandem cell), are systematically discussed. Nanomaterials, including oxides (such as TiO 2 , Ta 2 O 5 , Fe 2 O 3 and SrTiO 3 ) and nitrides (such as GaN, graphitic carbon nitride, and Ta 2 N 3 ), are investigated. It is shown that these strategies can generally apply to all of materials, such as oxide and nitride semiconductors. It is believed that maximal conversion efficiency could be achieved by optimizing the electronic structures of photocatalysts and engineering the structures of cells.

Principles on design and fabrication of nanomaterials as photocatalysts for water-splitting

Gallium-doped tungsten trioxide thin film photoelectrodes for photoelectrochemical water splitting

A new method for the fabrication of a bilayer WO3/Fe2O3 photoelectrode for enhanced photoelectrochemical performance

Bilayer n-WO3/p-Cu2O photoelectrode with photocurrent enhancement in aqueous electrolyte photoelectrochemical reaction

Enhanced plasmonic photoelectrochemical response of Au sandwiched WO3 photoanodes

The tungsten trioxide (WO3) and copper(II) oxide (CuO) photoelectrodes have been fabricated from acidic aqueous solution of peroxy-tungstate and basic aqueous solution of copper sulphate-lactic acid respectively, by electrodeposition method. The samples produced were calcined at 450 °C for 30 minutes before the deposition of second layer. The CuO was layered on WO3 sample by electrodeposition of basic aqueous solution of copper sulphate-lactic acid, followed by annealing process at 450 °C for 30 minutes. On the other hand, the WO3 layer was casted onto CuO sample by sol-gel method and it was annealed at 450 °C for 30 minutes. The resulting samples were then characterized by XRD to confirm their structures. Photoelectrochemical characterization of the WO3, CuO and WO3-CuO bilayer photoelectrodes were carried out under 100 W xenon light illumination, in 0.5 M sodium sulphate solution with saturated calomel electrode (SCE) reference electrode and platinum counter electrode. The PEC stability of the electrodes was evaluated at -0.7 V vs SCE under irradiated condition.

Kim Hang Ng

Papers

Gallium-doped tungsten trioxide thin film photoelectrodes for photoelectrochemical water splitting

A new method for the fabrication of a bilayer WO3/Fe2O3 photoelectrode for enhanced photoelectrochemical performance

Bilayer n-WO3/p-Cu2O photoelectrode with photocurrent enhancement in aqueous electrolyte photoelectrochemical reaction

Enhanced plasmonic photoelectrochemical response of Au sandwiched WO3 photoanodes

Stability of WO3/CuO Heterojunction Photoelectrodes in PEC System