In-situ synthesis of crystalline Ag-Nb2O5 nanobelt clusters with enhanced solar photo-electrochemical performance for splitting water

The crystalline hexagonal Nb 2 O 5 (H-Nb 2 O 5 ) nanobelt clusters dominantly exposed (−   110) facet are firstly synthesized by a hydrothermal topological reaction with a precursor of fiber-like K 2 Nb 2 O 6 ·H 2 O. The structure and morphology of samples obtained at different temperatures and times are investigated. There are two steps in the synthesis process. One is the acid-exchanging reaction transforming into amorphous phase protonated niobate (HNO), and the other is dehydration reaction transforming into H-Nb 2 O 5 , and simultaneous dissolution reaction which forms nanobelt cluster morphology from the fiber-like particle. The formation mechanism of H-Nb 2 O 5 nanobelt clusters has been proposed in detail. After photo-reduced reaction between the H-Nb 2 O 5 nanobelt clusters and AgNO 3 solution, the dominantly exposed (−   110) facet of H-Nb 2 O 5 nanobelt is homogeneously covered by Ag nanoparticles . The photo-electrochemical performance of the obtained H-Nb 2 O 5 nanobelt clusters and Ag deposited H-Nb 2 O 5 (Ag-Nb 2 O 5 ) nanobelt clusters as photocatalysts are evaluated by splitting water under simulated sunlight illumination, and the generated photocurrent of Ag-Nb 2 O 5 sample is 10.73   μA, which is 535 times that of the H-Nb 2 O 5 sample. The results demonstrate that the Ag-Nb 2 O 5 nanobelt clusters have a high photo-electrochemical performance as well as good sunlight photoelectric conversion efficiency.