Photoelectrochemical Catalysis of Waste Polyethylene Terephthalate Plastic to Coproduce Formic Acid and Hydrogen

A novel strategy for modulating the oxidation ability of the Fe 2 O 3 /Ni( OH ) x photoanode’s photogenerated holes was successfully introduced to realize the photoelectrochemical (PEC) catalysis of waste polyethylene terephthalate (PET) plastic for the first time. This PEC process achieved an up to ∼100% Faradaic efficiency of formic acid/formate. The underlying Ni 2+ /Ni 3+ redox couple-mediated mechanism was explored, which suggested that the introduction of the Ni( OH ) x cocatalyst can effectively tune the oxidation ability of the photogenerated holes to improve the selectivity toward the desired formic acid/formate products.