Electronic Engineering of ABO₃ Perovskite Metal Oxides Based on d⁰ Electronic‐Configuration Metallic Ions toward Photocatalytic Water Splitting under Visible Light

Abstract

Particulate photocatalytic water splitting is considered as one of the most promising and low‐cost routes toward green hydrogen production, toward which developing a semiconductor photocatalyst with a wide visible light response and high charge transfer velocity is the key issue. Metal oxides based on d 0‐configuration metal ions, especially those with the perovskite structure, are a group of ideal candidates toward photocatalytic water splitting, benefitting from their high structural stability, suitable conduction band minimum (CBM), and high carrier mobility. However, the main problems staggering the development of highly efficient photocatalysts are from the rather big bandgap of these d 0‐configuration metal oxides to cause limited UV light response and from the flexibly changed valence state of the d 0‐configuration metal cations in the B site of the perovskite structure. Various strategies are developed to address these problems, and the summary on electronic engineering strategies of the d 0‐metal‐based perovskite metal oxides toward visible light response and stable photocatalytic performance in this review is focused on. Finally, the construction of the photocatalytic overall water splitting (OWS) system based on these perovskite semiconductors is discussed and outlooked.

Theoretical insights into the effect of surface structure and anion ordering on the properties of SrTaO2N for photocatalytic water splitting

“…However, realistic photocatalysts do not show this perfect behavior. Based on the Gibbs free energy changes of Reactions (A)-(D), the overpotential of OER (η OER ) can be calculated by Equation (11): We have constructed and optimized HO*, O* and HOO* intermediates in OER, calculated the Gibbs free energy changes of four elementary steps, and drawn the corresponding diagrams of OER at pH = 0, T = 298 K and U = 0 V in Figures 8 and 9, respectively. The local structures of intermediates are displayed in each panel.…”

“…This family of compounds often adopt the ABO 3 perovskite structure with one of the O 2À ions replaced by a N 3À ion, and the B cation replaced by metals with higher cationic charge simultaneously. The band gap width of ABO 2 N can be tuned by using different combinations of elements at the A and B sites [10,11].…”

Single phase of perovskite YTaON2 synthesized for photocatalytic water reduction and oxidation under visible-light irradiation

“…Perovskite-structured materials with the general formula ABX 3 have been widely investigated for photocatalytic water splitting considering their high structural stability and the superb flexibility of their framework components. 8–10 The A sites are larger cations in the perovskite framework, which are usually occupied by alkali, alkaline earth, or rare earth cations, while the B sites as the smaller cations are usually occupied by transition metal cations. The anion at the X site performs 12-coordination with the A-site atom and 6-coordination with the B-site atom, and these AX 12 or BX 6 polyhedrons connect orderly to make up a stable crystal framework.…”

Theoretical Studies on Layered Perovskite Photocatalysts Sr2M2O7 (M = Nb and Ta) Modified by NiO Cocatalysts

“…In the past few decades, great efforts have been devoted to developing various semiconductor photocatalysts. Among them, perovskite-based materials have gained significant attention due to their compositional flexibility, good stability, and highly efficient photocatalytic activity. − The ideal perovskite oxide has a general formula of ABO 3 with a cubic structure, in which A and B sites can accommodate most of the metal elements in the periodic table . The rational combination or partial substitution of different metal ions at A and B sites extends the family of perovskite oxides and results in structural distortion and change in various properties.…”