Insight into interface chemistry of metal oxides anchored on biowaste-derived support for highly selective glycolysis of waste polyethylene terephthalate.

[Display omitted] • Mo-Zn@SiO 2 catalyst was simply prepared using a facile impregnation. • The Mo addition facilitates the formation of new catalytic active site of ZnMoO 4. • Adsorption energy is optimized over ZnMoO 4 surface to boost the PET depolymerization. • 5Mo-10Zn@SiO 2 exhibited 100% PET conversion and 90.4 % BHET at mild conditions. The unprecedented rise of polyethylene terephthalate (PET) waste demands sustainable solutions like catalytic glycolysis, a promising recycling technology that mitigates environmental harm. Herein, we synthesized a series of novel Mo-Zn@SiO 2 catalysts for PET glycolysis, derived from readily available rice husk ash via the wetness impregnation method. The optimum Mo-Zn@SiO 2 exhibits exceptional activity, achieving complete PET conversion and a 90.4 % yield of bis(2-hydroxyethyl) terephthalate (BHET) – one of the highest performances reported for heterogeneous catalysts. Density functional theory (DFT) calculations suggest that the formation of the ZnMoO 4 phase optimizes reactant and product adsorption energies, enhancing Lewis acidity and facilitating depolymerization. Kinetic studies reveal a low apparent activation energy (139.27 kJ/mol) for BHET production at 175–190 °C. Additionally, the catalyst demonstrates excellent recyclability, maintaining activity after five cycles. This work presents a viable and efficient strategy for PET waste valorization using a low-cost, readily available, and easily synthesized catalyst. [ABSTRACT FROM AUTHOR]