Rational Design of Branched WO₃ Nanorods Decorated with BiVO₄ Nanoparticles by All-Solution Processing for Efficient Photoelectrochemical Water Splitting

Abstract

The formation of heterostructure between BiVO4 and WO3 is a promising strategy to design a high-performance photoanode. In this study, we prepared the highly crystalline branched WO3 nanorods decorated with BiVO4 nanoparticles by all-solution processes and achieved high photoelectrochemical (PEC) performances through the morphological design of WO3 bottom layer and BiVO4 decorations. WO3 nanorods with epitaxially grown nanobranches could be prepared via two-step hydrothermal method, and the BiVO4/WO3 heterostructure was formed by sequent electrodeposition of BiVO4 nanoparticles on branched WO3 nanorods. In comparison to bare WO3 nanorods counterpart, the macelike branched WO3 nanorods can present the enlarged surface area and improved light trapping properties from the morphological control of WO3 hierarchical nanostructures, endowing a 32.8% higher photocurrent around 0.85 mA/cm2 at 1.23 V vs reversible hydrogen electrode (RHE). While decorated with BiVO4 nanoparticles, the as-fabricated BiVO4/macelike WO3 nanorod heterostructure performs a much improved photocurrent of 3.87 mA/cm2 at 1.23 V vs RHE. Such a significant enhancement may result from the significantly enhanced light-harvesting and charge separation efficiency. This rational design of heterostructured photoanodes provides a facile, cost-effective, and scalable strategy to improve PEC performances.

Type-II BiVO4/Ni3(hexahydroxytriphenylene)2 heterojunction photoanodes for effective photoelectrochemical reaction

“…BiVO 4 nanoparticles were coated onto FTO/glass substrates by a modified electrodeposition method. 18,19 The typical synthesis process includes an FTO/glass substrate, platinum (Pt) mesh, and Ag/AgCl/saturated NaCl as the working, counter, and reference electrodes, respectively. The precursor solution for BiVO 4 electrodeposition was prepared as follows.…”

Promoting Photoelectrochemical Activity and Stability of WO3/BiVO4 Heterojunctions by Coating a Tannin Nickel Iron Complex

“…Furthermore, the elemental mapping of the asprepared WO 3 /BiVO 4 @TANiFe (Figure 2e S3). 37 These results indicate that the WO 3 /BiVO 4 composites have been successfully prepared by the stepwise in situ cation exchange transformation. After coating the TANiFe layer, the XRD pattern (Figure 3a) shows no distinct change, suggesting the amorphous characteristic of the nanolayer.…”

Ferro-photocatalytic Enhancement of Photoelectrochemical Water Splitting Using the WO3/BiFeO3 Heterojunction

“…WO 3 shows at least five different crystalline structures in the temperature range of −180 to 900 °C, in which monoclinic is the most stable phase at room temperature among them with an indirect band gap energy (E g ) of 2.5−3.2 eV that can be conducive to the absorption of solar radiation in the visible region. 22 Nonetheless, long-term usage of the WO 3 photoanode gradually declines its photocatalytic activity because of the accumulation of peroxo species on its surface. 23 Moreover, weak visible-light absorbance of WO 3 (<460 nm) is another restriction of this semiconductor that deviates its conversion efficiency from the maximum theoretical value (∼6.3%).…”