Robust Superhydrophobic Laser-Induced Graphene for Desalination Applications

The fabrication of long-lived, durable, superhydrophobic surfaces using a manufacturable process is an important challenge for material science. Significant advances have been reported; however, many surfaces suffer from fragility, nonmanufacturable fabrication techniques, and temporal instability. Such challenges have limited commercial scale application of superhydrophobic films, including their application to water desalination where long lifetimes and durability are essential. The fabrication of controllably wettable surfaces formed from laser-induced graphene is demonstrated in atmospheric conditions with contact angle control from 59 degrees to 176 degrees; representing some of the most superhydrophobic carbon surfaces ever reported. This superhydrophobicity is used to engineer a membrane with the largest pores ever reported for the energy efficient water desalination technique of air-gapped membrane distillation. State-of-the-art production of distilled water is observed, and no membrane failure or loss of superhydrophobicity is observed on a time-scale of monthssuggesting total water production capabilities well beyond anything yet demonstrated.