Corrosion Engineering of Part‐Per‐Million Single Atom Pt₁/Ni(OH)₂ Electrocatalyst for PET Upcycling at Ampere‐Level Current Density

Abstract The plastic waste issue has posed a series of formidable challenges for the ecological environment and human health. While conventional recycling strategies often lead to plastic down‐cycling, the electrochemical strategy of recovering valuable monomers enables an ideal, circular plastic economy. Here a corrosion synthesized single atom Pt₁/Ni(OH)₂ electrocatalyst with part‐per‐million noble Pt loading for highly efficient and selective upcycling of polyethylene terephthalate (PET) into valuable chemicals (potassium diformate and terephthalic acid) and green hydrogen is reported. Electro‐oxidation of PET hydrolysate, ethylene glycol (EG), to formate is processed with high Faraday efficiency (FE) and selectivity (>90%) at the current density close to 1000 mA cm⁻² (1.444 V vs RHE). The in situ spectroscopy and density functional theory calculations provide insights into the mechanism and the understanding of the high efficiency. Remarkably, the electro‐oxidation of EG at the ampere‐level current density is also successfully illustrated by using a membrane‐electrode assembly with high FEs to formate integrated with hydrogen production for 500 h of continuous operation. This process allows valuable chemical production at high space‐time yield and is highly profitable (588–700 $ ton⁻¹ PET), showing an industrial perspective on single‐atom catalysis of electrochemical plastic upcycling.