Tungsten Oxide–reduced Graphene Oxide Composites for Photoelectrochemical Water Splitting

• Published in: Arabian journal for science and engineering (2011) 2021, Vol.46 (1), p.813-825
• Main Authors: Ansari, Shahzad Munir, Khan, M. Zubair, Anwar, H., Ikram, M., Sarfraz, Zahid, Alam, Naveed, Khan, Yaqoob
• Format: Article
• Language: English
• Subjects: Coated electrodes; Composite materials; Electrical properties; Electrical resistivity; Electrodes; Engineering; Graphene; Humanities and Social Sciences; Indium tin oxides; Morphology; multidisciplinary; Optical properties; Photoelectric effect; Photoelectric emission; Reflectance; Research Article-Physics; Science; Sheets; Spectroscopy; Spectrum analysis; Sunlight; Tungsten oxides; Water splitting
• ISSN: 2193-567X; 1319-8025; 2191-4281
• DOI: 10.1007/s13369-020-05011-6

Photoelectrochemical (PEC) water splitting is the latest technology to produce hydrogen and electricity by using sunlight. The low bandgap of tungsten oxide (WO 3 ) enables it as a suitable candidate for PEC water splitting. Reduced graphene oxide (rGO) is a material having extra thin sheets and a very large surface area with extreme conductivity. Graphene oxide (GO) has been synthesized by using a modified Hummer’s method. Hydrothermal reduction of GO gives rGO. WO 3 –graphene composites of different ratios have been prepared hydrothermally and then coated on indium tin oxide coated glass to make electrodes for water splitting. Various characterization techniques such as UV–visible spectroscopy, diffusion reflectance spectroscopy, X-ray diffraction, scanning electron microscopy, and linear sweep voltammetry (LSV) were used to study the absorbance/reflectance, structure, morphology, and optical/electrical properties of prepared nanostructures. In addition, WO 3 particles were distributed on the strong sheets of rGO randomly. The IV-measurements were taken of rGO/WO 3 electrodes under dark environment (very minor current ~ 250 nA) by using LSV. The electrodes exhibit maximum ~ 450 μA under dark environment, while photocurrent initiates from 1.0 mA to 3.2 mA under artificial sunlight. That is convincingly an exceptional result in the field of PEC cell.