Interfacial configurational entropy tuning strategy enabling liquid alloys for efficient depolymerization of polyolefin waste.

Abstract

Accumulation of plastic waste presents a global environmental crisis, posing severe threats to ecosystems. Depolymerization offers a promising route for closed-loop recycling of plastic waste. Nevertheless, depolymerizing chemically stable polyolefins remains challenging, yet fails to achieve high light olefin yields and stability. Herein, we propose an interfacial configurational entropy tuning strategy for liquid alloy catalysts, inducing active site interfacial enrichment and optimizing electronic structure. With this strategy, a quaternary GaInNiSn catalyst with medium entropy is developed for recycling polyolefins into light olefins under atmospheric pressure without co-reactant consumption, achieving a space-time yield of 181.5 mmol g_cat⁻¹ h⁻¹. Mechanistic insights reveal that Ni^δ⁻-Sn^δ+ active sites form within the dynamic Ga interface, enabling C-H bond activation to promote β-scission. Furthermore, a photovoltaics-driven depolymerization system is constructed, maintaining light olefin output of 52.8 L h⁻¹ over 120 hours. Our work unlocks a potent tool for efficient and sustainable plastic waste utilization.