Incorporating Ni-Polyoxometalate into the S-Scheme Heterojunction to Accelerate Charge Separation and Resist Photocorrosion for Promoting Photocatalytic Activity and Stability

Abstract

The emerging polyoxometalate (POM) nanomaterials are transition metal oxygen anion clusters with d0 electronic configurations, which could be attractive and potential photocatalysts. Hence, a nickel (Ni)-substituted polyoxometalate K6Na4[Ni4(H2O)2(PW9O34)2]·32H2O (Ni4POM)-incorporating step (S)-scheme heterojunction was developed to promote photocatalytic activity and stability in H2 and H2O2 production. The multielectron transfer through variable valence metal centers in Ni4POM would facilitate the recombination of invalid charges through the S-scheme pathway. Moreover, incorporating Ni4POM into the S-scheme heterojunction can broaden the light absorption range and meanwhile lead to resistance to photocorrosion to promote the optical and chemical stability of Cd0.5Zn0.5S (CZS). The optimized CZSNi-70 exhibited a H2 evolution rate of 42.32 mmol g–1 h–1 under visible-light irradiation with an apparent quantum yield of 32.27% at 420 nm and a H2O2 production rate of 295.4 μmol L–1 h–1 under 420 nm light-emitting diode irradiation. This work can provide a new view for the development of transition metal-substituted POM-based stable and efficient S-scheme photocatalysts.

Single‐Atom Phosphorus Defects Decorated CoP Cocatalyst Boosts Photocatalytic Hydrogen Generation Performance of Cd0.5Zn0.5S by Directed Separating the Photogenerated Carriers

“…Figure 2e shows the variation in microstructure of the CoP‐V p @CZS shell that a lot of nanoparticles loaded on the vertically aligned CoP‐V p nanoflakes, which are consistent with the results of FESEM tests (Figure 1f,g). From the HRTEM image of CoP‐V p @CZS (Figure 2f), nearly circular CZS nanoparticles with the size of ≈20 nm was marked by a blue dotted line and the two suits of interplanar spacing of 0.249 and 0.328 nm were recorded which ascribed to the (111) planes of CoP and CZS, [ 39 ] respectively. Similar structures were obtained between CoP and CZS in the same preparation method and labeled as CoP@CZS (Figure S6, Supporting Information).…”

Insights into atomic‐electronegativity‐controlled excited state intramolecular proton transfer behavior for the novel oxazolonapthoimidazo[1,2‐a]‐pyridine (ONIP) compound: A time‐dependent density functional theory study

“…From HOMO to LUMO transition, the electron density of the N atom moiety increases, whereas that of the donor O atom part decreases. In other words, ICT around hydrogen bonding moieties largely demonstrates the stronger ability of N atom to attract the H proton, which also facilitates the H proton to break away from O atom via photoexcitation 31–34 …”

Double Type-II Heterojunction MnS/Mn–Cd–S/Ni-Polyoxometalate for Improving Visible-Light-Driven H2 Production

“…15-Ni x –Mn 0.5 Cd 0.5 S composite and those of the corresponding Ni-POMs are shown in Figure . The typical IR features of Ni-POMs from 700 to 1100 cm –1 match the typical W–O and P–O vibrational bands of Ni-POM clusters. , Obviously, the composites have all of the typical peaks of Ni-POMs, which is an indication of the successful coupling of Mn 0.5 Cd 0.5 S and Ni-POMs. Furthermore, a minor red shift for the characteristic W–O and P–O vibrations of 15-Ni x –Mn 0.5 Cd 0.5 S was discovered, which might be attributed to the interaction between Ni-POMs clusters and the Mn 0.5 Cd 0.5 S.…”