Pyrite ( FeS 2 )‐decorated 1D TiO 2 nanotubes in a bilayer as a sustainable photoanode for photoelectrochemical water splitting activity

• Published in: Journal of the Chinese Chemical Society (Taipei) 2023-04, Vol.70 (4), p.857-868
• Main Authors: Alam, Noor, Zahid, Muhammad
• Format: Article
• Language: English
• ISSN: 0009-4536; 2192-6549
• DOI: 10.1002/jccs.202200540

Herein, FeS 2 @TiO 2 nanotubes photocatalyst was prepared by electrochemical anodization method followed by successive ionic layer adsorption and reaction method, and then finally annealed in a tube furnace for homogenous crystallization. The surface morphology, elemental composition, optical properties, and crystalline structure of the prepared FeS 2 @TiO 2 nanocomposite were found out by performing scanning electron microscopy, energy dispersive X‐ray spectroscopy, X‐ray diffraction, UV–Vis diffuse reflectance spectroscopy, and fluorescence spectroscopy, respectively, while bonds vibrations and various functional groups' presence were analyzed using Raman and Fourier transform infrared spectroscopy. A higher photocurrent density of 1.59 mA/cm 2 at 0.3 V versus reference electrode of Ag/AgCl (1.23 V versus reversible hydrogen electrode) using 100 mW/cm 2 intensive light source was shown by 15‐FeS 2 @TiO 2 nanotubes (uniformly loaded photoanode) while donor density (N D ) of 3.68 × 10 −13  cm −3 as compared to pure TiO 2 NTs (0.09 mA/cm 2 ), 05‐FeS 2 @TiO 2 NTs (0.19 mA/cm 2 ), 10‐FeS 2 @TiO 2 NTs (0.53 mA/cm 2 ) and 20‐FeS 2 @TiO 2 NTs (0.61 mA/cm 2 ), respectively. The exceptional photoelectrochemical activity results were attributed to the homogenous integration of FeS 2 that not only increase the charge separation but also, intensively interacted with the substrate (TiO 2 nanotubes), which results in an excellent photoelectrochemical activity.