Osmotic energy harvesting with soft-etched nanoporous polyimide membranes. (January 2022)

• Record Type: Journal Article
• Authors: Ali Haider, Muhammad H.; Nasir, Saima; Ali, Mubarak; Ramirez, Patricio; Cervera, Javier; Mafe, Salvador; Ensinger, Wolfgang
• Is Part Of: Materials today energy. Volume 23(2022)
• Publication Date: 2022-01
• Subjects: Soft-etching -- Heavy ion irradiation -- Reverse electrodialysis -- Nanopores -- Polymer foils -- Power generation; Energy development -- Periodicals; Energy industries -- Periodicals; Power resources -- Periodicals; Energy policy -- Periodicals; Energy development; Energy industries; Energy policy; Power resources; Electronic journals; Periodicals; 621.042
• DOI: 10.1016/j.mtener.2021.100909
• Languages: English
• ISSNs: 2468-6069

Abstract

Abstract: We present the study of osmotic energy harvesting with soft-etched nanoporous polyimide membranes for a wide range of salt concentration differences, ion irradiation fluences, and multipore orientations (parallel or network). The effect of solution pH and divalent cations on the membrane performance is also investigated. The membrane behavior is evaluated in terms of the reversal potential ( V rev ), the maximum power generation (Pmax ), and the energy conversion efficiency (ηmax ). For an exposed membrane area of ∼1 cm 2, the maximum values obtained for these parameters are V rev = 123 mV, Pmax = 0.45 μW, and ηmax = 40%, respectively. A significant decrease in the membrane performance is observed for membrane samples obtained with ion fluences higher than 4 × 10 9 ions cm −2 because of pore overlapping and the diffusional resistance of the external solution boundary layers at very low ionic concentrations. The soft-etched membranes are able to hold the reversal potential for several days. Graphical abstract: Image 1 Highlights: Nanoporous polyimide membranes are applied for energy harvesting under various concentration gradients. Performance is determined by reversal potential, maximum power generation, and energy conversion efficiency. Effect of ion fluences, nanopore orientation, solution pH, and divalent cations is investigated. The ability of membranes to hold the reversal potential for several days is studied.