Efficient Phase-Change Thermal Management Film Based on Dual-Network Phase-Change Microgels: Integrating Mechanical Strength, Self-Healing, Photothermal Responsiveness, and Desalination Performance

Energy shortage and water scarcity are global challenges, and integrating thermal energy storage with seawater desalination is an effective approach to address these issues. In this study, a phase-change thermal management film (PGPF) with excellent photothermal conversion capability was fabricated via a blending and doping process, combining double-network phase-change microgels (PSP), graphene oxide (GO), and poly(vinyl alcohol) (PVA). Inspired by the bioinspired flexible and strong adhesion mechanism of octopus tentacles, PSP was prepared and uniformly “welded” within the material through hydrogen bonding among PSP, GO, and PVA, forming a multinetwork structure. This design significantly enhances the mechanical properties of PGPF in saline environments (up to 130 MPa) and its self-healing ability, extending its service life during seawater desalination. PGPF efficiently converts solar energy into heat, exhibiting high photothermal conversion efficiency, enabling rapid temperature rise to high levels, and achieving efficient thermal evaporation. Under xenon lamp illumination simulating sunlight, the PGPF temperature quickly reaches 162 °C, demonstrating excellent photothermal performance, with an evaporation rate as high as 3.18 kg·m −2 ·h −1 . The material’s outstanding phase-change behavior and thermal stability indicate its promising potential for solar-driven seawater desalination applications.