A flexible anti-clogging graphite film for scalable solar desalination by heat localization

Abstract

Solar–thermal energy conversion is an economically promising route for power generation, desalination, and distillation. With the recent introduction of the heat localization concept, highly efficient solar harvesting has garnered more attention with accelerated research efforts. In this concept, the material structure localizes solar energy at the desired interface minimizing the heat loss by the bulk phase occurring in conventional solar bulk heating approaches. However, the development of materials for long-term solar desalination through heat localization remains an open challenge due to clogging of the structure after a short period of time. Herein, we report a new efficient and flexible material structure for solar desalination with anti-clogging characteristics. The material structure has a porous polymer skeleton with embedded graphite flakes and carbon fibers. The geometry of pores in this structure and anti-clogging coating prevent any salt accumulation in the material structure. We have demonstrated five orders of desalination of highly salty brine (1.52 × 10⁵ mg L⁻¹) in a long-term performance with no change in its efficiency. The performance of this structure in the laboratory and outside environment is assessed. This cost-effective and durable material along with its easy fabrication procedure provides a path towards large-scale efficient solar desalination.