Single-Atom Ni on Tungsten Oxides Drives Hydrogen Spillover for Efficient Plastic Waste Upcycling

Upcycling polyolefin waste into liquid fuels via hydrocracking demands cost-effective catalysts that integrate strong acidity with hydrogenation activity, necessitating precise atomic control of the catalytic sites. Here, we report a non-noble catalyst featuring atomically dispersed Ni on structurally engineered WO2.72 nanowires, where heterolytic Ni–O–W sites enable heterolytic H2 activation and hydrogen spillover. In situ infrared spectroscopy shows that active Bro̷nsted acidic W–OH groups form dynamically from terminal W═O species during hydrogen spillover, surpassing bridged W–OH-W species in WO3 for C–C bond cleavage. The optimized 1Ni/WO2.72 catalyst achieves complete polyethylene conversion at 240 °C with 94.3% selectivity toward gasoline- and jet-ranged liquid fuels and state-of-the-art productivity of 5.0 gliquid/gcat·h, outperforming noble metal catalysts. Time-resolved operando infrared spectroscopy captures a stepwise hydrocracking pathway involving dehydrogenation, protonation, and C–C bond cleavage, while kinetic studies and DFT modeling confirm the critical role of these engineered sites. This work establishes a design strategy for single-atom, non-noble bifunctional catalysts through atomic-scale engineering of oxide structures and metal nuclearity, offering both mechanistic insight and practical guidance for plastic waste upcycling.