Ultrathin FeOOH Nanolayers with Abundant Oxygen Vacancies on BiVO₄ Photoanodes for Efficient Water Oxidation

Abstract

Photoelectrochemical (PEC) water splitting is a promising method for storing solar energy in the form of hydrogen fuel, but it is greatly hindered by the sluggish kinetics of the oxygen evolution reaction (OER). Herein, a facile solution impregnation method is developed for growing ultrathin (2 nm) highly crystalline β-FeOOH nanolayers with abundant oxygen vacancies on BiVO photoanodes. These exhibited a remarkable photocurrent density of 4.3 mA cm at 1.23 V (vs. reversible hydrogen electrode (RHE), AM 1.5 G), which is approximately two times higher than that of amorphous FeOOH fabricated by electrodeposition. Systematic studies reveal that the excellent PEC activity should be attributed to their ultrathin crystalline structure and abundant oxygen vacancies, which could effectively facilitate the hole transport/trapping and provide more active sites for water oxidation.

Rational Design and Construction of Cocatalysts for Semiconductor‐Based Photo‐Electrochemical Oxygen Evolution: A Comprehensive Review

“…[33,73,101,[171][172][173][174][175][176] It has potential advantages such as feasible synthesis, well stability, and resource abundancy. [33,73,101,[171][172][173][174][175][176] It has potential advantages such as feasible synthesis, well stability, and resource abundancy.…”

Solar Water Splitting under Neutral Conditions Using Z‐Scheme Systems with Mo‐Doped BiVO4 as an O2‐Evolving Photocatalyst

“…We have previously reported the effectiveness of the loading of a CoO x cocatalyst, which works as a water‐oxidation site to O 2 on BiVO 4 in a Z‐scheme system with RGO as an electron mediator and CuGaS 2 as a H 2 ‐evolving photocatalyst . In addition to the Co cocatalysts, FeO x and NiO x have also been reported as an effective cocatalyst for oxidation of water to O 2 on a BiVO 4 photoelectrode . Accordingly, CoO x , FeO x , and NiO x cocatalysts were loaded on BiVO 4 and BiVO 4 :Mo(0.25%), and the loading effect on the Z‐schematic water‐splitting activity was investigated, as shown in Table .…”

A Plasma‐Triggered O−S Bond and P−N Junction Near the Surface of a SnS2 Nanosheet Array to Enable Efficient Solar Water Oxidation

“…[14] Fore xample,T ian et al constructed ah eterointerface of N-SnS 2 on P-CuInS 2 nanosheets. [17] In view of the high cost and low earthabundance of precious metals,various OER co-catalysts were also synthesized, such as CoPi, [18] FeOOH, [19] Co 3 O 4 , [20] NiO, [21] MnO x , [22] and so on. Constructing the co-catalyst layer on the photoelectrode can promote the OER process and reduce the surface recombination.…”