An Efficient ZnIn₂S₄@CuInS₂ Core–Shell p–n Heterojunction to Boost Visible-Light Photocatalytic Hydrogen Evolution

Abstract

The efficient separation of photoexcited electrons and holes is crucial for improving the activity of photocatalytic hydrogen evolution. Herein, an efficient core−shell p−n heterojunction of ZnIn 2 S 4 @CuInS 2 microflowers has been devised and fabricated by two-step hydrothermal method. The results revealed that the marigold-like microspheres of ZnIn 2 S 4 @CuInS 2 heterojunction consisted of thin nanosheets, matched well in the lattice, and had a large interface contact area, which boosted charge separation and transfer for solar hydrogen production. Moreover, the intimate interfacial contact between n-type ZnIn 2 S 4 and p-type CuInS 2 resulted in the formation of unique p−n heterojunction, which further promoted charge separation due to the built-in electric field. As a consequence, the ZnIn 2 S 4 @CuInS 2 photocatalyst with 5 atom % CuInS 2 showed the highest production of H 2 evolution (about 1168 μmol•g −1 ) among all prepared photocatalysts, which was nearly 4-fold the amount of the hydrogen production for the pristine ZnIn 2 S 4 . Therefore, the core−shell p−n heterojunction is an efficient structure design for the utilization of solar energy to obtain clean energy.

Gradient Hydrogen Migration Modulated with Self-Adapting S Vacancy in Copper-Doped ZnIn2S4 Nanosheet for Photocatalytic Hydrogen Evolution

“…ZnIn 2 S 4 is a promising layered transition metal chalcogenide for photocatalytic hydrogen evolution, which has attracted many researchers because of its unique layered structure and stability. − In this study, atomic Cu doping in ZnIn 2 S 4 nanosheets (Cu–ZIS) with simultaneous Vs creation was fabricated elaborately for photocatalytic hydrogen evolution. In the following, we determined the substituting sites of Cu doping and confirmed the behavior mechanism around Cu sites from experimental results and theoretical simulations.…”

Amorphous WP‐Modified Hierarchical ZnIn2S4 Nanoflowers with Boosting Interfacial Charge Separation for Photocatalytic H2 Evolution

“…[ 14,15 ] However, the hydrogen evolution activity of ZnIn 2 S 4 is still not ideal due to the sluggish carrier migration kinetics and restrictive light capture capability. [ 16 ] In order to improve the efficiency of solar energy for producing hydrogen from water splitting, many methods have been adopted to improve the photocatalytic activity of ZnIn 2 S 4 , such as morphology regulation, [ 17–19 ] element doping, [ 20,21 ] heterojunction construction, [ 22–26 ] and loading cocatalysts. [ 27–32 ] For example, Xing et al.…”

NiS Cocatalyst–Modified ZnIn2S4 as Ohmic‐Junction Photocatalyst for Efficient Conversion of CO2

“…[14][15][16][17][18][19][20][21][22] Among these traditional and popular semiconductors, ZnIn 2 S 4 as a low-cost ternary metal sulfide has been applied in photocatalytic reduction of CO 2 field owing to its suitable bandgap, good light resistance, and excellent photoelectric characteristics. [23,24] In addition, compared with independent 1D and 2D, the 3D ZnIn 2 S 4 assembled by ultrathin structures provides superior specific surface area and enriches CO 2 -adsorption sites, thereby improving the ability to anchor CO 2 molecules. [25][26][27] At present, 3D ZnIn 2 S 4 -based composite photocatalyst have become a hot spot in the area of photocatalysis.…”