Photoelectrodes Based upon Mo:BiVO₄ Inverse Opals for Photoelectrochemical Water Splitting

Abstract

BiVO4 has been regarded as a promising material for photoelectrochemical water splitting, but it suffers from a major challenge on charge collection and utilization. In order to meet this challenge, we design a nanoengineered three-dimensional (3D) ordered macro-mesoporous architecture (a kind of inverse opal) of Mo:BiVO4 through a controllable colloidal crystal template method with the help of a sandwich solution infiltration method and adjustable post-heating time. Within expectation, a superior photocurrent density is achieved in return for this design. This enhancement originates primarily from effective charge collection and utilization according to the analysis of electrochemical impedance spectroscopy and so on. All the results highlight the great significance of the 3D ordered macro-mesoporous architecture as a promising photoelectrode model for the application in solar conversion. The cooperating amplification effects of nanoengineering from composition regulation and morphology innovation are helpful for creating more purpose-designed photoelectrodes with highly efficient performance.

A colloidoscope of colloid-based porous materials and their uses

“…For example, Zhou et al demonstrated enhancement in the photocurrent density and photoelectrochemical water splitting efficiency for 3D ordered macroporous Mo:BiVO 4 inverse opal structures as compared to the porous but disordered counterpart (Figure 26). 25 This enhancement was attributed to the synergistic effects of compositional and structural optimization, leading to an improvement in charge transport properties. 25 Reproduced with permission from the American Chemical Society.…”

“…25 This enhancement was attributed to the synergistic effects of compositional and structural optimization, leading to an improvement in charge transport properties. 25 Reproduced with permission from the American Chemical Society.…”

Enhanced photoelectrochemical and photocatalytic activities of CdS nanowires by surface modification with MoS2 nanosheets

“…In general, the increase of charge carrier density is associated with increased electrical conductivity (σ) of the photoelectrode, which is given by σ=enµ, where e, n and µ are the electronic charge, the concentration and mobility of charge carrier, respectively. A high mobility is highly favorable for improving charge separation and transport [43,45].…”

Determination of the Intrinsic Defect at the Origin of Poor H2 Evolution Performance of the Monoclinic BiVO4 Photocatalyst Using Density Functional Theory

“…13 Doping by introducing an extrinsic defect through the addition of a transition-metal cation or an anion can increase the carrier density and thus improve the conductivity for optimum photocatalytic performance. Following 4 this strategy, numerous studies and research efforts have been focused on doping BiVO 4 with Mo and W. [14][15][16][17] This effect has been extended as well to intrinsic doping defined as native defects. Some studies suggested that this oxide can be stoichiometric at 1 atmospheric oxygen pressure, while oxygen vacancies might be created in reducing conditions.…”