Highly crystalline anatase TiO2 nanotubes array films enhanced with Bi2S3 for photoelectrochemical applications

The synthesis of bismuth (III) sulphide (Bi2S3)-sensitized titanium dioxide nanotubes arrays (TiO2 NTAs) was carried out using the SILAR (successive ionic layer adsorption and reaction) method. The effect of different cycles on the performance of a photoanode made of Bi2S3/TiO2 NTAs in photoelectrochemical cells was investigated. Field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy and UV–visible spectroscopy were used to investigate Bi2S3/TiO2 NTs morphological, elemental composition, structural and optical absorption, respectively. TiO2 nanotubes had a tetragonal crystal structure, whereas Bi2S3 had an orthorhombic crystal structure, according to XRD measurements. Absorbance spectra showed that the absorbance edges shifted towards longer wavelengths as the number of cycles increased, showing that the optical properties had significantly improved following deposition. Bi2S3/TiO2 NTAs photoanode was proposed as a viable alternative photoanode in photoelectrochemical applications. The photocurrent density of the Bi2S3/TiO2 NTAs composite film grew first, then declined as the number of Bi2S3 deposition cycles increased. After three cycles of deposition of Bi2S3, the Bi2S3/TiO2 composite films displayed the highest photoelectrochemical characteristics. The photocurrent density of Bi2S3-3Cy/TiO2 NTAs was 1.427 mA cm–2, about four times that of plain TiO2 NTAs. The Bi2S3/TiO2 NTAs photoanode was offered as a feasible alternative photoanode in photoelectrochemical applications based on the findings of this study.