Ti–Fe2O3/Ni(OH) as an efficient and durable photoanode for the photoelectrochemical catalysis of PET plastic to formic acid

Photoelectrochemical (PEC) technology provides a promising prospect for the transformation of polyethylene terephthalate (PET) plastic wastes to produce value–added chemicals. The PEC catalytic systems with high activity, selectivity and long–term durability are required for the future up–scaling industrial applications. Herein, we employed the interfacial modification strategy to develop an efficient and stable photoanode and evaluated its PEC activity for ethylene glycol (EG, derived from PET hydrolysate) oxidation to formic acid. The interfacial modification between Fe2O3 semiconductor and Ni(OH)x cocatalyst with ultrathin TiOx interlayer not only improved the photocurrent density by accelerating the kinetics of photogenerated charge carriers, but also kept the high Faradaic efficiency (over 95% in 30 h) towards the value–added formic acid product. This work proposes an effective method to promote the PEC activity and enhance the long–term stability of photoelectrodes for upcycling PET plastic wastes.