Constructing 1,2,4-Triazole Based Porphyrin Photocatalyst for Efficient Degradation of Rhodamine B

• Novel 1,2,4-triazole sulfonic acid porphyrin photocatalyst synthesized. • TBSAFPc displayed a 97% degradation efficiency of Rhodamine B. • Optimized parameters revealed: 10 ppm, 0.2 g/L TBSAFPc, pH 5 in 180 min. • TOC of the degraded RhB sample was 82.92% attained. • The optimized parameter effectively degraded 250mL RhB with 84.26% efficiency. The increasing discharge of synthetic dyes into aquatic systems poses serious environmental concern due to their toxicity and resistance to conventional treatment methods. In this context, the development of efficient, metal-free, and sustainable photocatalysts is highly desirable. Herein, a novel 1,2,4-triazole-based sulfonic acid functionalized porphyrin (TBSAFPc) was successfully synthesized via the reaction of triazole ionic liquid and pyrrole under reflux conditions in the presence of glacial acetic acid. The prepared TBSAFPc was confirmed by 1 H NMR, 13 C NMR, PXRD, FT-IR, SEM techniques. The Hammett acidity, and energy band gap (DRS) were determined by UV-Visible Spectrophotometer while surface area was studied by BET method. The photocatalytic performance of TBSAFPc was investigated for the degradation of Rhodamine B (RhB) under irradiation with a low-power 5 W LED light source in a homemade photo-chamber under ambient conditions. The catalyst exhibited excellent photodegradation efficiency of 97 % for a 10 ppm RhB solution without the use of any additive under optimized conditions. Scavenger experiments confirmed the formation of active species responsible for degradation. The degradation process was further supported by UV–Visible analysis, FT-IR identification of intermediates, and a significant reduction in total organic carbon (TOC) up to 82.92%. A plausible photocatalytic mechanism was proposed based on experimental findings. Importantly, the heterogeneous TBSAFPc catalyst demonstrated good stability and recyclability for five successive runs, as confirmed by 1 H NMR and FT-IR analysis. Furthermore, under optimized conditions, mass-scale degradation (250 mL) achieved 84.26% degradation efficiency, highlighting its potential for practical wastewater treatment applications. Visible-Light Photocatalytic RhB Degradation