Ultrathin Two-Dimensional ZnIn₂S₄/Ni_x-B Heterostructure for High-Performance Photocatalytic Fine Chemical Synthesis and H₂ Generation

Abstract

Photocatalytic H2 evolution coupled with organic transformation provides a new avenue to cooperatively produce clean fuels and fine chemicals, enabling a more efficient conversion of solar energy. Here, a novel two-dimensional (2D) heterostructure of ultrathin ZnIn2S4 nanosheets decorated with amorphous nickel boride (Ni x -B) is prepared for simultaneous photocatalytic anaerobic H2 generation and aromatic aldehydes production. This ZnIn2S4/Ni x -B catalyst elaborately combines the ultrathin structure advantage of the ZnIn2S4 semiconductor and the cocatalytic function of Ni x -B. A high H2 production rate of 8.9 mmol h–1 g–1 is delivered over the optimal ZnIn2S4/Ni x -B with a stoichiometric production of benzaldehyde, which is about 22 times higher than ZnIn2S4. Especially, the H2 evolution rate is much higher than the value (2.8 mmol h–1 g–1) of the traditional photocatalytic half reaction of H2 production with triethanolamine as a sacrificial agent. The apparent quantum yield reaches 24% at 420 nm, representing an advanced photocatalyst system. Moreover, compared with traditional sulfide, hydroxide, and even noble metal modified ZnIn2S4/M counterparts (M = NiS, Ni­(OH)2, Pt), the ZnIn2S4/Ni x -B also maintains markedly higher photocatalytic activity, showing a highly efficient and economical advantage of the Ni x -B cocatalyst. This work sheds light on the exploration of 2D ultrathin semiconductors decorated with novel transition metal boride cocatalyst for efficient photocatalytic organic transformation integrated with solar fuel production.

Visible-light-driven anaerobic oxidative upgrading of biomass-derived HMF for co-production of DFF and H2 over a 1D Cd0.7Zn0.3S/NiSe2 Schottky junction

“…The positive slope exhibits the n-type semiconductor properties of the blank Cd 0.7 Zn 0.3 S. The E fb value for the Cd 0.7 Zn 0.3 S samples is approximately estimated to be −1.1 eV ( vs. Ag/AgCl). Since the conduction band minimum (CBM) of the n-type semiconductor is about 0.1 eV more negative than E fb , 56 the conduction band potential ( E CB ) of Cd 0.7 Zn 0.3 S is found to be about −1.2 eV ( vs. Ag/AgCl). 34 Based on the formula of E CB ( vs. the RHE) = E ( Ag/AgCl ) + 0.196 + 0.0591 × pH (pH = 6.8), the E CB value of −0.60 eV vs. the RHE for blank Cd 0.7 Zn 0.3 S can be obtained.…”

“…4b, the semicircle diameter of Cd 0.7 Zn 0.3 S/NiSe 2 4% is smaller than that of Cd 0.7 Zn 0.3 S, indicating a lower charge transfer resistance and more efficient surface charge migration. 56 Furthermore, to confirm that NiSe 2 can provide active sites to promote the surface H 2 evolution reaction, the linear sweep voltammetry (LSV) approach is utilized to investigate the proton reduction activities of Cd 0.7 Zn 0.3 S and Cd 0.7 Zn 0.3 S/NiSe 2 4%. As shown in Fig.…”

CoP decorated 2D/2D red phosphorus/B doped g-C3N4 type II heterojunction for boosted pure water splitting activity via the two-electron pathway

“…It is well known that tight chemical coupling at the interface between different materials can promote interfacial charge separation and transfer. [65][66][67][68] To clarify the existence of chemical coupling in CoP/RP/BCN, the P 2p spectra of RP/ BCN and CoP/BCN were measured. The spectrum in Fig.…”

Latest Progress on Photocatalytic H2 Production by Water Splitting and H2 Production Coupled with Selective Oxidation of Organics over ZnIn2S4-Based Photocatalysts

“…After visible light illumination for 4 h, the optimal 0.5% Au/ZnIn 2 S 4 nanosheets yielded H 2 (326.68 μmol) and benzaldehyde (352.04 μmol) simultaneously. Henceforth, lots of ZnIn 2 S 4 -based dual-functional photocatalysts have been developed to fulfill H 2 production with simultaneous oxidation of benzyl alcohol with high selectivity and good stability, such as Co-doped ZnIn 2 S 4 nanotubes, Ni-loaded ZnIn 2 S 4 flowers, Ni 12 P 5 /ZnIn 2 S 4 with Zn vacancies, Ni 12 P 5 /O-doped ZnIn 2 S 4 , and Ni X -B/ZnIn 2 S 4 . Because of the superior separation efficiency of charge carriers and high redox capacity of the left photoexcited electrons and holes induced by the Z-scheme heterojunction, ZnIn 2 S 4 -based direct Z-scheme heterostructures, including CeO 2 /ZnIn 2 S 4 composite, phosphomolybdic acid (HPM) cluster-incorporated ZnIn 2 S 4 (HPM/ZIS) nanosheets, WO 3 /ZnIn 2 S 4 1D/2D composite, and the O-ZnIn 2 S 4 /TiO 2– x S-scheme heterojunction, all exhibit good activity for concurrent H 2 generation and selective oxidation of benzyl alcohol.…”