Boosting photocatalytic efficiency: LDH modified with gambier leaf extract for tetracycline degradation

Environmental pollution due to pharmaceutical waste, particularly antibiotics such as tetracycline (TC), is a global concern as it can lead to bacterial resistance. Photodegradation using Layered Double Hydroxide (LDH)-based photocatalysts offers an environmentally friendly solution to address this issue. In this study, LDH with a variety of trivalent cations (NiM 3+ (M 3+ = Al, Fe, Cr)) was modified with gambier leaf extract ( Uncaria gambir ) through the restacking-delaminating method. This modification aims to reduce band gap energy, improve structural stability, and increase TC photodegradation efficiency. Characterization was performed using XRD, FT-IR, UV-DRS, BET, and SEM. The results showed that the modification with gambir extract successfully increased the UV light absorption and decreased the band gap to 1.60–1.63 eV. Photodegradation tests showed that the degradation efficiency increased significantly, with NiAl-G achieving the highest efficiency of 63.34 % under optimum conditions (pH 7, mass 30 mg, temperature 50°C). Kinetics studies showed that the reaction followed the Langmuir-Hinshelwood model, with an increased reaction rate after modification. These results confirmed that LDH-G has great potential as an eco-friendly photocatalyst for antibiotic remediation in aquatic environments.