Hierarchical structures of GO-supported BiBTC MOFs for efficient RhB photodegradation

Abstract

This study, we synthesized a graphene oxide@BiBTC MOF (GO@BiBTC) photocatalyst in situ using a hydrothermal method. The resulting samples were comprehensively characterized using FT-IR, Raman spectra, XRD, SEM, TEM, XPS and UV-Vis spectroscopy. The photodegradation reaction fits the pseudo-first-order kinetics and the deterioration rate constants (k) value of BiBTC, GO@BiBTC MOF composites were 0.03 and 0.07 min⁻¹, respectively. The GO@BiBTC MOF composite demonstrated a reduced energy band gap compared to BiBTC, with values of 3.39 eV and 3.6 eV, respectively. Among the various samples, the optimized GO@BiBTC MOF demonstrated superior photocatalytic performance, achieving a 98% degradation rate of rhodamine B (RhB) within 60 min, outperforming the pure BiBTC MOF. The significantly enhanced photocatalytic activity of BiBTC@GO can be attributed to its enhanced charge transfer and adsorption-(photo) degradation. Furthermore, the outstanding photo-stability of the GO@BiBTC MOF photocatalyst was investigated by conducting recycling measurements consecutively over five cycles for RhB with 90% photodegrading efficiency.