Development of CdS/TNTA nanocomposite to improve performance of simultaneous electrocoagulation-photocatalysis process for hydrogen production and ciprofloxacin elimination

Abstract

This study aimed to enhance the effectiveness of the simultaneous combination of electrocoagulation and photocatalysis processes by modifying the configuration of the photocatalyst. A heterojunction mechanism was developed by integrating CdS with a photocatalyst using a TiO₂ nanotube array (TNTA) [1]. This mechanism is designed to enhance photocatalytic efficiency by reducing electron-hole recombination. The successful synthesis of CdS/TNTA nanocomposite was confirmed using various characterization methods, including XRD, HRTEM, FESEM, UV–Vis DRS, PL, transient photocurrent, and XPS. The results showed that CdS/TNTA worked better than TNTA in a single photocatalysis process, achieving improved Ciprofloxacin (CIP) removal (7.9 % to 13.8 %) and hydrogen gas production (0.006 to 0.156 mmol/m²plate). Simultaneously operating electrocoagulation and photocatalysis systems in the respective optimized settings resulted in significant enhancements. Hydrogen gas yield increased by 44 % (from 443 to 636 mmol/m² plate) compared to using only TNTA, while CIP removal improved from 79 % to 83 %. This study demonstrates that the synthesis of CdS/TNTA photocatalysts may be a promising approach to achieving high performance of hydrogen recovery while simultaneously removing CIP from wastewater.