MXene/硬脂酸定型相变复合材料的太阳能光热储能性能OA

Conventional organic phase change materials(PCMs)often suffer from leakage during solid-liquid transitions and limited solar absorption,which restrict their practical application in thermal energy management.To address these challenges,this study presents a facile composite design combining chemical cross-linking and freeze-drying techniques.Stearic acid(SA),serving as the phase change component,is effectively encapsulated together with two-dimensional MXene nanosheets,which possess superior photothermal conversion properties,within a three-dimensional porous polyvinyl alcohol(PVA)network,resulting in a shape-stabilized photothermal composite PCM.Comprehensive characterization using scanning electron microscopy(SEM),X-ray diffraction(XRD),and Fourier-transform infrared spectroscopy(FT-IR)confirmed the uniform and stable immobilization of SA within the PVA matrix and demonstrated excellent compatibility among components.Thermal energy storage performance,thermal stability,and photothermal conversion were further evaluated using differential scanning calorimetry(DSC),thermogravimetric analysis(TGA),UV-vis-NIR spectrophotometry,and simulated solar irradiation.The incorporation of MXene increased light absorption by approximately 350 percent,enabling efficient solar harvesting and photothermal conversion.The composite maintained superior shape stability with no observable leakage for SA mass fraction up to 75%,while achieving a high latent heat of 112.56 J/g.In addition,it exhibited excellent thermal stability and cycling durability.This work establishes a robust and scalable strategy for fabricating leakage-proof,solar-responsive PCMs,providing a solid experimental foundation for advanced thermal energy management systems that integrate solar harvesting,thermal storage,and controlled energy release.