Evaluating the potential of superhydrophobic nanoporous alumina membranes for direct contact membrane distillation.

Hypothesis: Direct contact membrane distillation (DCMD) processes exploit water-repellant membranes to desalt warm seawaters by allowing only water vapor to transport across. While perfluorinated membranes/coatings are routinely used for DCMD, their vulnerability to abrasion, heat, and harsh chemicals necessitates alternatives, such as ceramics. Herein, we systematically assess the potential of ceramic membranes consisting of anodized aluminum oxide (AAO) for DCMD.

Hierarchically porous titania thin film prepared by controlled phase separation and surfactant templating.

Poly(propylene glycol) (PPG) of moderately high molecular weight (M(n) = 3500 Da) exhibits amphibious behavior in aqueous solution in that it is hydrophilic at low temperature but hydrophobic at high temperature. This property is utilized to generate porous titania thin films with a hierarchical structure consisting of macroporous voids/cracks in films with mesoporous walls. The smaller mesopores result from the self-assembly of the Pluronic block copolymer P123 to form micellar templates in well-ordered arrays with hexagonal symmetry.