Synthesis and Characterizations of n type Bi2O3 and BiVO4 Based Semiconductors for Their Applications in Photoelectrochemical Processes

Abstract

Meeting the colossal global energy demand by utilizing clean renewable newlineenergy resources can lead to sustainable future. The photocatalytic water splitting newlinegained interest in recent times due to its huge capability for clean hydrogen newlineproduction through an eco-friendly and cost-effective manner. The development of newlinephoto-electrode materials with the capability of absorbing the visible and UV-Vis light newlineand promoting water oxidation and reduction reaction becomes the essential newlinerequirement. Significant overpotential is required for the photoelectrodes to drive this newlinereaction making the water oxidation process more challenging. This thesis focuses on newlinethe development of photoanode material in a straightforward and economically newlinefriendly manner and the study of the as-prepared photoelectrodes. In this section, my newlinethesis entitled quotSynthesis and characterizations of n-type Bi2O3 and BiVO4-based newlinesemiconductors for their applications in photoelectrochemical processesquot, deep newlinedives into the development of suitable n-type semiconductor materials for newlinephotoelectrochemical oxygen production. The main theme of the thesis is the facile newlinesynthesis of photoanode materials with appropriate band gap energy for water newlineoxidation reaction, along with the exploration of their physicochemical and newlineelectrochemical properties. Bismuth-based binary and ternary metal oxides are newlinedeveloped for the photocatalytic water oxidation reaction. The effect of metal doping newline(Mo, W) in the matrix, composite formation with some additive (e.g. g-C3N4), and newlinesurface modification by Co(II) are also investigated. newlineThe main achievements of this thesis are presented in Chapter 2-6. newlineIn the initial approach, bismuth (III) oxide (Bi2O3) semiconductor was newlinedeveloped by varying the calcination temperature (200-800°C) using Bi(NO3)3 as a newlineprecursor. Physico-chemical characterization and photocatalytic experiments newlineconfirmed that the sample annealed at an optimized temperature of 650°C and newlinedemonstrates the highest photo-activity to degrade Rhodamine B as