Efficient Photocatalytic Charge Separation at Anatase–Hematite Heterojunctions with a Tuned Three-Dimensional Cocatalytic NiO Support
T.C. Bhagya, Liju Elias, Sreedharan V. Manoj, S.M.A. Shibli
Abstract
The present study explores a design strategy of loading active materials into porous cocatalytic supports for accomplishing rapid charge separation for photocatalytic hydrogen generation. Herein, a three-dimensional ternary heterostructure is developed through in-situ formation of photocatalytically active nanoparticles inside porous Ni templates with exposed NiO as an efficient and stable photocatalyst. The design merit lies in rapid charge separation through NiO cocatalysts and availability of abundant active sites for efficient and sustained hydrogen generation. The introduction of NiO and the coexistence of active phases inside the porous NiO have modified the electronic structure and reduced the charge transfer resistance. This could facilitate the formation of more heterojunctions for faster interfacial charge transfer and enhanced visible light absorption characteristics. The optimal characteristics have enabled the three-dimensional ternary heterostructure for realizing a substantial hydrogen generation of 1438 μmol h–1, with an apparent quantum efficiency of 31.74%. The present methodology opens up new horizons, providing more insights and opportunities for extending contribution to structural designing of hierarchical architectures for large-scale energy-related applications.