<p>The growing pressure on global energy and freshwater resources necessitates continuous innovation in resource management technologies to ensure long-term sustainability. Solar energy, as a widely accessible and renewable resource, is of strategic importance for sustainable development. This has driven advancements in photothermal membrane distillation (PMD), which integrates interfacial solar conversion with phase-change separation. However, under prolonged exposure to hypersaline feed solutions, solute accumulation at the thermal interface of hydrophobic membranes often leads to crystalline deposition within micropores. This results in irreversible membrane fouling and a severe decline in permeate flux stability. Aimed at resolving this issue, a highly salt-resistant PTFE/PEGDA/graphene hydrogel composite membrane was developed. In this design, a PEGDA hydrogel forms a hydrophilic cross-linked polymer network that reduces membrane surface adhesion to salt crystals. The incorporation of graphene further inhibits crystal adhesion on the inner pore walls and mitigates excessive local concentration, thereby enhancing resistance to salt crystallization. The water production performance of this composite membrane was evaluated under varying light intensities. In low-concentration brine, water production increased by nearly 35%. The enhancement was even more pronounced at higher salinities, with a production increase of nearly 74%, the water production rate reached 2.08&#xa0;kg·m⁻²·h⁻¹. The membrane distillation system maintained strong salt resistance over 3&#xa0;h of operation, and the desalination rate of the produced water exceeded 99.9%. These results demonstrate that the PTFE/PEGDA/graphene hydrogel composite membrane significantly improves membrane surface resistance to salt crystallization, thereby greatly enhancing system stability and efficiency in high-salinity environments.</p>