Synthesis of In2Se3 homojunction photocatalyst with α and γ phases for efficient photocatalytic performance

Herein, novel γ-In2Se3 nanoparticle/α-In2Se3 nanosheet (In2Se3 NPS) homojunctions were constructed by a facile solvothermal method and applied to photocatalytic H2 production from water splitting and removel of Cr(VI) pollutant for the first time. The photocatalytic H2 evolution rate and Cr(VI) removal rate can reach 1347.6 μmol/(g·h) and 94.9% in 10 min without any co-catalyst over optimal In2Se3 NPS, which is 4.34 and 4.12 times higher than that of pure γ-phase In2Se3 nanoparticles. The characterizations of valence band X-ray photoelectron spectroscopy and Mott-Schottky measurement prove that the In2Se3 NPS homojunction establishes a staggered band alignment to promote the separation and transfer of photogenerated charge carriers. Meanwhile, the hybrid nanoparticle/ nanosheet structure with appropriate proportion, uniform distribution and intimate contact can boost the light trapping and provide more electron trapping sites, resulting in active photocatalytic performance. This work not only enrich In2Se3-based semiconductor nanomaterials with a simple synthetic route, but also provide a new sight in design homojunction for efficient photocatalytic applications.