A unique scandium oxide-doped cobalt oxide nanosheet array for coupling hydrogen evolution with catalytic conversion...

Upgrading polyethylene terephthalate (PET) plastic waste into value-added chemicals through electrocatalysis is an effective way to alleviate environmental pollution and the energy crisis. Herein, we developed a unique scandium oxide-doped cobalt oxide nanosheet array loaded on foam nickel ((ScCo)O_x/NF), which synergistically promotes both the hydrogen evolution reaction (HER) and the ethylene glycol oxidation reaction (EGOR), thereby enabling the integrated production of green H₂ and upgrading of plastic waste. Benefiting from the unique interfacial effects, the cathodic (ScCo)O_x/NF catalyst achieves a current density of 10 mA cm^-2 at an overpotential as low as 79 mV. The anodic (ScCo)O_x/NF catalyst exhibited an electrode potential of 1.23 V (vs. RHE) at a current density of 10 mA cm^-2. Under the condition of applying an electric potential of 1.5 V, the Faradaic efficiency of formate production reached 92.8 %. Density functional theory (DFT) calculations highlight the synergistic interaction between Sc₂O₃ and Co₃O₄, which effectively lowers the reaction barrier and thereby enhances the catalytic activity in EGOR. This study successfully developed a novel bifunctional catalyst through the strategic design of doping scandium into cobalt oxide, offering a green and sustainable approach for the high-value conversion of PET.