PHOTONIC-ENHANCED DESALINATION USING GRAPHENE-COATED MEMBRANES HARNESSING SOLAR-INDUCED VAPOR DYNAMICS FOR SCALABLE, LOW-ENERGY WATER SECURITY SOLUTIONS

Freshwater scarcity poses a critical global challenge, exacerbated by population growth, industrialization, and climate change. Conventional desalination techniques such as reverse osmosis and multi-stage flash distillation are effective but are highly energy-intensive and infrastructure-dependent, limiting their application in low-resource or off-grid regions. This study proposes and systematically evaluates a novel photonic-enhanced desalination method utilizing graphene-coated membranes that harness solar-induced vapor dynamics for efficient water purification. The design leverages graphene’s exceptional photothermal properties—including broadband solar absorption, high thermal conductivity, and structural tunability—to maximize interfacial heat localization and evaporation rates while minimizing thermal losses to the bulk fluid. Experimental results under 1-sun solar simulation demonstrate a significant enhancement in evaporation flux (1.82 kg/m²·h), with energy conversion efficiency exceeding 85%, outperforming conventional polymeric and uncoated membranes by over 60%. The system maintains operational stability over repeated cycles, with minimal salt accumulation and membrane degradation. A comparative literature review of underscores the progression of photothermal desalination technologies and highlights the unique advantages of graphene-based systems in addressing scalability and durability limitations. Additionally, techno-economic modeling indicates that this membrane-integrated system is well-suited for modular deployment in decentralized water treatment infrastructures, particularly in arid and coastal regions. The findings suggest that photonic-enhanced desalination using graphene membranes represents a promising direction toward low-energy, scalable, and climate-resilient water security solutions.