Strain Adjustment Realizes the Photocatalytic Overall Water Splitting on Tetragonal Zircon BiVO₄

Abstract

Overall water splitting to generate H 2 and O 2 is vital in solving energy problem. It is still a great challenge to seek efficient visible light photocatalyst to realize overall water splitting. In this work, the tetragonal zircon BiVO 4 is prepared by epitaxial growth on FTO substrate and its overall water splitting reaction is studied. Under the influence of epitaxial strain, the conduction band position shifts negatively and beyond H + /H 2 reduction potential (0 V vs NHE), which enables it to possess the photocatalytic hydrogen evolution activity. After loading cocatalysts, the overall water splitting (𝝀 > 400 nm) is realized (H 2 : ≈65.7 μmol g −1 h −1 , O 2 : ≈32.6 μmol g −1 h −1 ), and the value of solar hydrogen conversion efficiency is 0.012%. The single-particle photoluminescence (PL) spectra and PL decay kinetics tests demonstrate the cocatalysts are beneficial to the separation and transfer of carriers. The new strategy of adjusting the band structure by strain is provided.

Overall Utilization of Photoexcited Charges for Simultaneous Photocatalytic Redox Reactions

“…Nevertheless, owing to the complex electron transfer steps and high energy barrier. The poor H2 evolution performance and apparent quantum efficiency (AQE) lead to hard implications of photocatalytic OWS (Table 1) [118][119][120][121][122][123][124][125][126][127][128][129][130][131][132][133][134][135][136][137] .…”

Review on BiVO4-Based Photoanodes for Photoelectrochemical Water Oxidation: The Main Influencing Factors

“…Bismuth vanadate (BiVO 4 ), as the most promising PEC water oxidation photoanode material, has been attracting researchers’ attention in recent years. − It possesses a narrow band gap that allows it to absorb more visible light. In addition, the valence band position and the conduction band position of BiVO 4 photoanode are, respectively, close to 2.5 and 0 V versus reversible hydrogen electrode (RHE) due to the empty Bi 6p track that overlaps the back-key V 3d-O 2p track, which has strong catalytic capacity of oxygen production (Figure a) .…”

Constructing a bifunctional MoO2/Co heterojunction for efficient electrocatalytic hydrogen evolution and hydrazine oxidation

“…[14][15][16][17][18][19] However, the practical utilization of electrocatalytic water splitting to generate hydrogen is limited by the intrinsically sluggish kinetics of the anodic oxygen evolution reaction (OER, 4OH À / O 2 + 2H 2 O + 4e À , 1.23 V vs. RHE) involving multi-step proton-coupled electronic processes. 18,[20][21][22][23] Hence, the development and design of new electrocatalysts for both cathode and anode reactions has become a research hotspot. 24 Recently, it has been demonstrated that the oxidation of thermodynamically favorable organic small molecules, such as urea, [25][26][27] hydrazine, [28][29][30] ethanol, 31,32 and 5-hydroxymethylfurfural, 33,34 instead of the oxygen evolution reaction, can effectively improve the anode reaction efficiency and achieve hydrogen production at a lower voltage.…”

“…14–19 However, the practical utilization of electrocatalytic water splitting to generate hydrogen is limited by the intrinsically sluggish kinetics of the anodic oxygen evolution reaction (OER, 4OH − → O 2 + 2H 2 O + 4e − , 1.23 V vs. RHE) involving multi-step proton-coupled electronic processes. 18,20–23 Hence, the development and design of new electrocatalysts for both cathode and anode reactions has become a research hotspot. 24…”