Efficient photocatalytic degradation of rhodamine B by amorphous MOF-coated hydrogenated titanium dioxide core-shell photocatalyst coupled with peroxymonosulfate activation

In this study, a one-dimensional core–shell photocatalyst composed of hydrogenated TiO 2 (H-TiO 2 ) coated with an amorphous metal–organic framework (MOF) was synthesized via a simple hydrothermal method and applied as an efficient peroxymonosulfate (PMS) activator for Rhodamine B (RhB) degradation. Under simulated sunlight irradiation for 20 min, the optimized H-TiO 2 /BPDC*2 catalyst achieved 99.40 % RhB removal at an initial concentration of 100 mg/L. Its apparent kinetic rate constant was 4.28 and 1.06 times higher than those of H-TiO 2 and H-TiO 2 /BPDC, respectively. The enhanced performance is attributed to the core–shell heterojunction structure, which improves light absorption and charge separation, as evidenced by increased photocurrent, reduced photoluminescence intensity, and shorter time-resolved photoluminescence (TRPL) decay. Furthermore, the catalyst exhibited excellent stability over multiple cycles, demonstrating strong potential for practical wastewater treatment applications. Mechanistic studies revealed that ·O 2 − and 1 O 2 were the dominant reactive species involved in the degradation process.