Facile and robust construction of a 3D-hierarchical NaNbO 3-nanorod/ZnIn 2S 4 heterojunction towards ultra-high photocatalytic H 2 production

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

The robust 3D-hierarchical NaNbO ₃-nanorod/ZnIn ₂S ₄ heterojunction shows a striking H ₂-evolution rate of 30.04 mmol h ⁻¹ g ⁻¹ under sunlight, the highest among reported NaNbO ₃ and ZnIn ₂S ₄-based photocatalysts to date.

Abstract

It is imperative but still challenging to develop heterojunction photocatalysts for efficient interfacial charge carrier separation in photocatalytic hydrogen evolution (PHE) reactions. Encouragingly, in this work, we constructed a 3D hierarchical NaNbO ₃/ZnIn ₂S ₄ heterojunction for the first time by in situ coating thin-layered ZnIn ₂S ₄ nanosheets on the external surface of NaNbO ₃ nanorods via a facile solvothermal method. A striking hydrogen evolution rate of 30.04 mmol h ⁻¹ g ⁻¹ was attained using NaNbO ₃/ZnIn ₂S ₄ as a photocatalyst under simulated sunlight irradiation, which is almost 110-fold and 11-fold higher than that of bare NaNbO ₃ and ZnIn ₂S ₄, respectively, and is the highest value obtained thus far among reported NaNbO ₃ and ZnIn ₂S ₄-based catalysts. This extraordinary improvement in the photocatalytic performance is mainly due to two reasons. Firstly, the difference in conduction band position and the intimate contact between NaNbO ₃ and ZnIn ₂S ₄ facilitate interfacial charge separation from NaNbO ₃ to ZnIn ₂S ₄. Secondly, the unique hierarchical heterostructure not only affords a more diffused surface area but also serves as a 3D supporting platform to generate more fruitful proton reduction sites, realizing a maximized photocatalytic activity. Additionally, density functional theory (DFT) calculations on the heterojunction further revealed the electron density distribution at the heterointerface and a close-to-neutral Gibbs free energy of hydrogen adsorption (Δ G _H). Hence, the present work can provide fresh guidance for the synthesis and development of more NaNbO ₃ and ZnIn ₂S ₄-based composite photocatalysts for related applications in photocatalysis.

Related collections

Most cited references 60

Record: found
Abstract: found
Article: not found

Construction of ZnIn2S4–In2O3 Hierarchical Tubular Heterostructures for Efficient CO2 Photoreduction

Xiong Lou, Bu Guan, Sibo Wang (2018)

We demonstrate the rational design and construction of sandwich-like ZnIn2S4-In2O3 hierarchical tubular heterostructures by growing ZnIn2S4 nanosheets on both inner and outer surfaces of In2O3 microtubes as photocatalysts for efficient CO2 photoreduction. The unique design integrates In2O3 and ZnIn2S4 into hierarchical one-dimensional (1D) open architectures with double-heterojunction shells and ultrathin two-dimensional (2D) nanosheet subunits. This design accelerates the separation and transfer of photogenerated charges, offers large surface area for CO2 adsorption, and exposes abundant active sites for surface catalysis. Benefiting from the structural and compositional merits, the optimized ZnIn2S4-In2O3 photocatalyst exhibits outstanding performance for reductive CO2 deoxygenation with considerable CO generation rate (3075 μmol h-1 g-1) and high stability.

0 comments Cited 339 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Metal-Free Photocatalyst for H2 Evolution in Visible to Near-Infrared Region: Black Phosphorus/Graphitic Carbon Nitride

Liang Mao, Xinchen Wang, Junying Zhang … (2017)

In the drive toward green and sustainable chemistry, exploring efficient and stable metal-free photocatalysts with broadband solar absorption from the UV to near-infrared region for the photoreduction of water to H2 remains a big challenge. To this end, a binary nanohybrid (BP/CN) of two-dimensional (2D) black phosphorus (BP) and graphitic carbon nitride (CN) was designed and used as a metal-free photocatalyst for the first time. During irradiation of BP/CN in water with >420 and >780 nm light, solid H2 gas was generated, respectively. Owing to the interfacial interaction between BP and CN, efficient charge transfer occurred, thereby enhancing the photocatalytic performance. The efficient charge-trapping and transfer processes were thoroughly investigated with time-resolved diffuse reflectance spectroscopic measurement. The present results show that BP/CN is a metal-free photocatalyst for artificial photosynthesis and renewable energy conversion.