Growth of CuO rods on kanthal coil via direct heating for photocatalytic degradation of rhodamine B

This study introduces a novel direct heating (DH) method for immobilizing Cu₂O and CuO nanomaterials onto kanthal coils, offering a scalable and efficient approach to photocatalyst synthesis. The coil achieved 100 % surface coverage within 4–8 min heating duration. Both the Cu₂O and CuO phases are present, and each has a narrow band gap, making them effective reductive photocatalysts. The CuO/coil prepared at 40 W heating power for 8 minutes exhibited Cu₂O particles (1666.67 ± 727.78 nm) and CuO rods (77.77 ± 19.08 nm in diameter), achieving a 21.01 % degradation efficiency for RhB dye under UV light. Despite agglomeration of Cu₂O particles limiting active sites, this method demonstrates simplicity and rapid synthesis compared to conventional techniques. Reusability tests revealed a decline in removal efficiency to 13.24 % after three cycles, attributed to photocatalyst detachment and dye accumulation on active sites. Addressing these challenges with improved adhesion and surface optimization could enhance long-term performance. The DH method shows strong potential for industrial wastewater treatment, offering a cost-effective and scalable solution for degrading organic pollutants. • The coil achieved 100 % surface coverage within 4–8 min heating duration. • Both the Cu₂O and CuO are narrow band gap semiconductor, making them effective reductive photocatalysts. • It demonstrated positive removal on the RhB dye. • DH method offers rapid and low cost approach for potential upscale synthesis.