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Abstract We demonstrate a novel approach of utilizing methanol (CH₃OH) in a dual role for (1) the methanolysis of polyethylene terephthalate (PET) to form dimethyl terephthalate (DMT) at near‐quantitative yields (~97 %) and (2) serving as an in situ H₂source for the catalytic transfer hydrogenolysis (CTH) of DMT to p‐xylene (PX, ~63 % at 240 °C and 16 h) on a reducible ZnZrO_xsupported Cu catalyst (i.e., Cu/ZnZrO_x). Pre‐ and post‐reaction surface and bulk characterization, along with density functional theory (DFT) computations, explicate the dual role of the metal‐support interface of Cu/ZnZrO_xin activating both CH₃OH and DMT and facilitating a lower free‐energy pathway for both CH₃OH dehydrogenation and DMT hydrogenolysis, compared to Cu supported on a redox‐neutral SiO₂support. Loading studies and thermodynamic calculations showed that, under reaction conditions, CH₃OH in the gas phase, rather than in the liquid phase, is critical for CTH of DMT. Interestingly, the Cu/ZnZrO_xcatalyst was also effective for the methanolysis and hydrogenolysis of C−C bonds (compared to C−O bonds for PET) of waste polycarbonate (PC), largely forming xylenol (~38 %) and methyl isopropyl anisole (~42 %) demonstrating the versatility of this approach toward valorizing a wide range of condensation polymers. 

This perspective examines site-proximity and intermediate transport effects in tandem CO₂hydrogenation, outlines strategies to boost CH₃OH selectivity, modulate rates and hydrocarbon pools, and provides a roadmap for next-generation catalyst design.