Solar water splitting over Rh_0.5Cr_1.5O₃-loaded AgTaO₃ of a valence-band-controlled metal oxide photocatalyst

Abstract

One-step photoexcitation type solar water splitting with a valence-band-controlled metal oxide photocatalyst.

A Water‐Splitting System with a Cobalt (II,III) Oxide Co‐Catalyst‐Loaded Bismuth Vanadate Photoanode Along with an Organo‐Photocathode

“…Water photolysis is known to be the most optimal procedure for acquiring solar hydrogen. Since the discovery of the water splitting system comprising a titanium(IV) dioxide (TiO 2 ) photoanode by Honda and Fujishima, [1] numerous studies on water splitting by both photoelectrochemical and photocatalytic methods have been conducted [2–12] . As a long‐standing issue, the development of active photocatalyst materials, which are able to efficiently utilize the solar spectrum for high output of molecular hydrogen, is required.…”

50 Years of Materials Research for Photocatalytic Water Splitting

“…In the same way, also Zn 1.44 GeN 2.08 O 0.38 decorated with RuO 2 was reported for overall water splitting, [40] and photodeposition of Rh 2‐y Cr y O 3 also resulted in water splitting activity [38] . Recently, AgTaO 3 was decorated with a similar co‐catalyst with defined stoichiometry, Rh 0.5 Cr 1.5 O 3 , resulting in overall water splitting with an apparent quantum yield of 40 % at 340 nm an a solar‐to‐hydrogen efficiency of 0.13 % [41] …”

“…[38] Recently, AgTaO 3 was decorated with a similar co-catalyst with defined stoichiometry, Rh 0.5 Cr 1.5 O 3 , resulting in overall water splitting with an apparent quantum yield of 40 % at 340 nm an a solar-to-hydrogen efficiency of 0.13 %. [41] Searching for visible light absorbing materials, TiO 2 played an important role in materials research. A very prominent strategy in the early 2000s was non-metal doping of stable and well-known oxides, [42] including TiO 2 , with e. g. nitrogen and/or sulfur anions.…”

Highly crystalline Na0.5Bi0.5TiO3 of a photocatalyst valence-band-controlled with Bi(iii) for solar water splitting

“…16 We have also reported that Rh 0.5 Cr 1.5 O 3 -loaded AgTaO 3 (BG 3.4 eV) shows high AQY (38% at 340 nm) and STH (0.13%) for water splitting. 17 The valence band maximum (VBM) of the Al-doped SrTiO 3 is formed by O2p orbitals, while that of the AgTaO 3 is formed by Ag4d orbitals. 18 A photocatalyst whose valence band (VB) is formed by orbitals of elements except oxygen like AgTaO 3 is called a valence-band (VB)-controlled photocatalyst.…”

“…18 A photocatalyst whose valence band (VB) is formed by orbitals of elements except oxygen like AgTaO 3 is called a valence-band (VB)-controlled photocatalyst. 3,17,19 The VBcontrolled photocatalyst is very important from the viewpoint of extension of responsive wavelength. Although the STH of the Rh 0.5 Cr 1.5 O 3 -loaded AgTaO 3 is the highest among the VBcontrolled photocatalysts, the BG of the AgTaO 3 is wider than that of the Al-doped SrTiO 3 .…”