Sheng-Peng Hu

Monodisperse SnS2 Nanosheets for High-Performance Photocatalytic Hydrogen Generation

Graphene-like two-dimensional layered materials have attracted quite a lot of interest because of their sizable band gaps and potential applications. In this work, monodisperse tin disulfide (SnS2) nanosheets were successfully prepared by a simple solvothermal procedure in the presence of polyvinylpyrrolidone (PVP). Large PVP molecules absorbing on (001) facets of SnS2 would inhibit crystal growth along [001] orientation and protect the product from agglomeration. The obtained SnS2 nanosheets have diameters of ca. 0.8-1 μm and thicknesses of ca. 22 nm. Different experiment parameters were carried out to investigate the transformation of phase and morphology. The formation mechanism was proposed according to the time-dependent experiments. SnS2 nanosheets exhibit high photocatalytic H2 evolution activity of 1.06 mmol h(-1) g(-1) under simulated sunlight irradiation, much higher than that of SnS2 with different morphologies and P25-TiO2. Moreover, the as-obtained SnS2 nanosheets show excellent photoelectrochemical response performance in visible-light region.

Ca(II) doped β-In2S3 hierarchical structures for photocatalytic hydrogen generation and organic dye degradation under visible light irradiation

Hierarchical structures assembled by two-dimensional (2D) nanosheets could inherit the characteristics of nanosheets and acquire additional advantages from the unique secondary architectures, which would have important influences on the photocatalytic properties of semiconductor nanomaterials. In this work, we successfully synthesized Ca(II) doped β-In2S3 hierarchical structures stacked by thin nanosheets by a simple solution chemical process. The effects of reaction temperature and Ca2+ concentration on the size and morphology of the products were systematically investigated. The photocatalytic applications of the β-In2S3 hierarchical structures were evaluated for hydrogen production and degradation of Rhodamine B (RhB) under visible light irradiation (λ>420nm). The β-In2S3 hierarchical structures showed promising activity towards photocatalytic hydrogen production (145.0μmolg-1h-1) and RhB solution (1×10-5M) was completely degraded within 100min under visible light irradiation.

Solution-phase synthesis of γ-In2Se3 nanoparticles for highly efficient photocatalytic hydrogen generation under simulated sunlight irradiation

Hexagonal indium selenide (γ-In2Se3) nanoparticles were successfully synthesized by a hot-injection method using triethylene glycol as a solvent. The structure and morphology of the obtained nanoparticles were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Phase-pure γ-In2Se3 nanoparticles could be obtained at a relatively low temperature of 220 °C. Further increasing the reaction temperature leads to enhanced crystallinity of the γ-In2Se3 nanoparticles, which favors improving the photocatalytic activity. The γ-In2Se3 nanoparticles synthesized at 250 °C exhibit excellent and stable photocatalytic hydrogen generation under simulated sunlight irradiation, which might be attributed to the strong absorbance both in the UV and visible light regions as well as their nano-sized morphology.