Electrochimica Acta, Vol.299, 357-365, 2019
Synthesis of oxygen deficient bismuth oxide photocatalyst for improved photoelectrochemical applications
The present paper reports the effect of nitrogen modification on photoelectrochemical (PEC) water oxidation behavior of Bi2O3 semiconductor thin film. The semiconductor particles were synthesized via hydrothermal route using Bi(NO3)(3) as a Bi-3(+) ion precursor and urea as the nitrogen source followed by drop-cast the particles and annealing the film at 600 degrees C. The synthesized Bi2O3 exhibited band gap energy of 3.01 eV, calculated from the UV-visible absorption spectrum which decreases to 2.75 eV through N-modification. Water oxidation behavior of the material has been tested through linear sweep voltammetry under periodic illumination. Highest photo-current of 180 mu Acm(-2) has been measured for water oxidation reaction at 0.95 V vs. Ag/AgCl, under illumination of 35 mWcm(-2). N-incorporation can enhance the photocurrent up to 50% whereas the visible responsiveness of the material improves significantly as confirmed from electrochemical action spectra and UV-visible absorption spectra. The photocatalytic activity of the semiconductor particles was confirmed through decoloration of Rhodamine-B dye, by spectrophotometric measurements. (C) 2019 Elsevier Ltd. All rights reserved.
Keywords:Hydrothermal synthesis;N-modification;Bismuth oxide photocatalyst;Oxygen vacancies;PEC water oxidation