Synthesis and characterization of Nb2O5@C core-shell nanorods and Nb2O5nanorods by reacting Nb(OEt)5via RAPET (reaction under autogenic pressure at elevated temperatures) technique

Abstract

Abstract The reaction of pentaethoxy niobate, Nb(OEt) 5 , at elevated temperature (800 °C) under autogenic pressure provides a chemical route to niobium oxide nanorods coated with amorphous carbon. This synthetic approach yielded nanocrystalline particles of Nb 2 O 5 @C. As prepared Nb 2 O 5 @C core-shell nanorods is annealed under air at 500 °C for 3 h (removing the carbon coating) results in neat Nb 2 O 5 nanorods. According to the TEM measurements, the Nb 2 O 5 crystals exhibit particle sizes between 25 nm and 100 nm, and the Nb 2 O 5 crystals display rod-like shapes without any indication of an amorphous character. The optical band gap of the Nb 2 O 5 nanorods was determined by diffuse reflectance spectroscopy (DRS) and was found to be 3.8 eV.