Construction of flourinated-TiO2 nanosheets with exposed {001} facets/CdSe-DETA nanojunction for enhancing visible-light-driven photocatalytic H2 evolution

Abstract

Although much significant efforts have been devoted to design highly efficient photocatalysts for addressing energy crisis and environmental issues, it remains challenging to construct a promising and efficient heterostructure among semiconductors for photocatalytic hydrogen (H2) production under visible-light excitation. Herein, the novel structure with 2D fluorinated-TiO2 nanosheets (F–TiO2 NSs) decorated CdSe-diethylenetriamine nanoflowers (CdSe-DETA NFs) was designed and fabricated by a simple and fast microwave-assisted hydrothermal method. The F–TiO2/CdSe-DETA heterojunction displays enhanced photocatalytic activity in splitting water to produce H2. Among them, 20%F–TiO2/CdSe-DETA exhibited the highest H2 evolution rate (12381 μmmol g−1 h−1), which is 2.92 and 6.44 times greater than that of pristine CdSe-DETA and CdSe, respectively. Meanwhile, 20%F–TiO2/CdSe-DETA composite shows a good stability in the cyclic runs for photocatalytic H2 evolution. The enhanced activity and reusability are primarily attributed to rapid separation of charge carriers, enrich catalytic active sites as well as strong light absorption capability. Besides, the in-situ growth of a certain amount F–TiO2 NSs with exposed {0 0 1} high-energy facets on surface of inorganic-organic CdSe-DETA NFs greatly helps to strengthen intimate interfacial contact. These results may furnish a reference to fabricate the heterostructures on the basis of CdSe that is extremely insightful for conversion of solar power to H2 energy.