W⁵⁺–W⁵⁺ Pair Induced LSPR of W₁₈O₄₉ to Sensitize ZnIn₂S₄ for Full‐Spectrum Solar‐Light‐Driven Photocatalytic Hydrogen Evolution

Abstract

The localized surface plasmon resonances (LSPR) effect makes W 18 O 49 an effective visible and near-infrared (NIR) light antenna to realize full-spectrum solar-light driven photocatalysis, yet the precise origin remains elusive. Here, the LSPR originates from the localized electron confinement around lattice W 5+ -W 5+ pairs in the unique structure of W 18 O 49 by density-functional theory calculation, which gives W 18 O 49 a broad absorption ranging from visible to NIR region, independent of the particle shape and size is confirmed. This unique periodic LSPR simplifies the design of W 18 O 49 -sensitized photocatalytic composite into enhancing the light absorbance of W 18 O 49 and screening photocatalytic semiconductors with suitable energy band potentials. To this end, hierarchical-structure W 18 O 49 microflowers with high absorbance have been coated with ZnIn 2 S 4 nanosheets to achieve cocatalyst-free photocatalytic composite, which presents an outstanding H 2 production rate of 902.57 µmol within 3 h under simulated solar-light. Comprehensive characterizations, including ultrafast transient absorption spectroscopy, prove the injection of hot electrons from W 18 O 49 to ZnIn 2 S 4 and the increase of long-lived active electrons. This work clarifies the LSPR origin of oxygen-deficient semiconductors and paves the way for the search of broad-spectrum active photocatalyst.

Enhanced Photoelectrocatalytic Water Splitting in Bi2Mo1–xWxO6 Solid Solutions: Understanding the Atomic Level Mechanism from the Experimental and First-Principles Approach

“…The effect of bandgap on W incorporation was studied by UV–vis diffuse reflectance and the results are shown in Figure a; the Bi 2 MoO 6 and Bi 2 WO 6 have absorption edges of 480 and 440 nm, and calculated bandgap energy of 2.65 and 2.83 eV respectively (eq S4). Upon introducing W, the absorption edges of Bi 2 Mo 1– x W x O 6 solid solutions show the redshift, but the change is very minimal and the results correlate well with previous reports. ,, Moreover, the CBM and VBM of Bi 2 Mo 1– x W x O 6 solid solutions were calculated (eqs S5–S6) from results of Mott–Schottky plots (Figure S7) and XPS valence band analysis ,− (Figure S8) and results are given in Figure c and Table S3, which indicates that when the small amount of Mo replaced by W there is no appreciable change in the band structure; meanwhile, it suggests that the influence of W is higher in the conduction band states than the valence band, which is further confirmed by the band structure analysis using DFT calculations. The DFT results clearly explain that the VBM of the Bi 2 MoO 6 and Bi 2 WO 6 mainly consists of O-2p and Bi-6s orbitals and CBM mainly originated from Mo-4d or/and W-5d orbitals, respectively.…”

Mo‐Modified ZnIn2S4@NiTiO3 S‐Scheme Heterojunction with Enhanced Interfacial Electric Field for Efficient Visible‐Light‐Driven Hydrogen Evolution

“…Emphasized that the exceptional activity of Mo 1.4 -ZIS@NTO is much greater than the previously reported ZnIn 2 S 4 -based photocatalysts for PHE (Figure 3d and Table S1, Supporting Information). [17,39,43,44] Thus, it is necessary to modify composition and heterojunction by extra elements to improve the overall photocatalytic performance.…”

Efficient interfacial electron transfer induced by hollow-structured ZnIn2S4 for extending hot electron lifetimes

“…S3, ESI†) can be assigned to the (102) and (104) lattice planes of hexagonal ZnIn 2 S 4 , respectively, which is consistent with previous reports. 23 This delicate structural design of the photocatalyst restrains the self-assembly and aggregation of 2D ultrathin ZIS nanosheets, ensuring the short migration distance of photogenerated carriers. Imposingly, hollow-structured ZIS-HNCs can also facilitate the light-absorption performance by internal multiple light scattering to enhance the PHE.…”