Materials design and mechanistic insights for advancing marine oil spill cleanup by photothermal absorbents

Photothermal oil absorbents (PTOAs) represent an innovative solution for marine oil spill pollution by using solar energy to reduce heavy crude oil viscosity, thereby enhancing oil absorption efficiency. However, an in-depth understanding of the mechanisms governing oil absorption and the structure-performance relationship remains underexplored. This review systematically examines the influence of morphology and compositions on absorbent key performance indicators, including absorption capacity, absorption rate, thermal conductivity, and environmental safety, with a focus on oil absorption mechanisms of PTOAs. This review also offers a comparative evaluation of PTOAs reported over the past five years, identifying their advantages and limitations. It highlights the key challenges and proposes future development directions for PTOAs, emphasizing innovative design strategies to enhance their applicability in the sustainable treatment of offshore oil spills. By providing insights and an action driven guide map for achieving high-performance and eco-friendly PTOAs, this review contributes significantly to advancing sustainable solutions for global marine oil spill mitigation. • Provide deep understanding of mechanisms governing oil absorption in PTOAs. • Establish structure-performance relationships in PTOAs with various morphologies. • Comparative evaluation of PTOAs in past five years with advantages and limitations. • Outlining key challenges and future research directions for PTOAs. • Suggesting strategies for engineering new PTOAs for sustainable oil spills cleanup.