Topological synthesis of crystalline Ag/T‐Nb 2 O 5 nanobelts with enhanced solar photoelectrochemical properties for splitting water

The tetragonal phase Nb 2 O 5 (T‐Nb 2 O 5 ) nanobelts with preferentially exposed the (010) facet have been successfully prepared for the first time by insitu topological reaction using the KNb 3 O 8 nanobelts as the precursor. Meanwhile, the transformation mechanism of the crystal structure and morphology from the layered KNb 3 O 8 nanobelt to the T‐Nb 2 O 5 nanobelt was revealed in detail by using XRD, FE‐SEM, TEM, HRTEM, SAED, UV‐vis DRS, EDX, XPS, and Raman spectra. In addition, Ag deposited T‐Nb 2 O 5 (Ag/T‐Nb 2 O 5 ) nanobelts were prepared by photo‐reduction reaction. The photoelectrochemical properties of the T‐Nb 2 O 5 nanobelts and Ag/T‐Nb 2 O 5 nanobelts as a photocatalyst were evaluated by splitting water under simulated sunlight. The results show that the photocurrent density generated by the prepared Ag/T‐Nb 2 O 5 sample is 48.1 µA∙cm −2 , which is 2.3 times that of the T‐Nb 2 O 5 sample, and the prepared tetragonal phase T‐Nb 2 O 5 nanobelts produce a photocurrent value 1.5 times that of the contrast orthogonal phase O‐Nb 2 O 5 nanosheets. It indicates that the (010) facet of the tetragonal phase Nb 2 O 5 is one of the highest photocatalytic active surfaces, and the visible light utilization efficiency of the T‐Nb 2 O 5 nanobelt with Ag deposited on the surface has been significantly improved, which implies that it has potential applications in the field of photocatalysis.