Controllable Synthesis of h-WO3 Nanoflakes by L-lysine Assisted Hydrothermal Route and Electrochemical Characterization of Nanoflakes Modified Glassy Carbon Electrode

Abstract

Hexagonal tungsten trioxide (h-WO3) nanoflakes have been synthesized by a hydrothermal approach using L-lysine as the shape directing agent. The influence of hydrothermal reaction time and L-lysine content on the morphology of h-WO3 was investigated. The experimental results showed that the nanoflake morphology could be achieved at higher concentration of L-lysine. Based on the evolution of nanoflake morphology as a function of hydro-thermal duration, a “dissolution-crystallization-Ostwald ripening” growth mechanism has been proposed. The electro-chemical performance of h-WO3 nanoflakes has also been investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It is found that h-WO3 modified glassy carbon electrode (GCE) showed lower charge transfer resistance and enhancement in peak current attributed to the enrichment in electroactive surface area and faster electron transfer kinetics at h-WO3 modified GCE.