This paper presents a review of recent publications on mathematical modeling, steady-state and dynamic behavior, and control of polyelectrolyte membrane and solid oxide fuel cells. We limited the scope of this review to these two fuel cell types, which have been studied more, and have been reported to be more promising, than other fuel cell types. Zero-, one-, two-, and three-dimensional models developed to describe the behavior of the fuel cells are reviewed. Essential components of these models are highlighted. Conditions under which a fuel cell exhibits steady state multiplicity are described. Stability of the steady states is discussed. Processes that take place inside the fuel cells and contribute to the existence of multiple time-scales in the fuel cells are examined. Control configurations and strategies proposed and used for the fuel cells are reviewed, and advantages and disadvantages of each are listed. At the end, in view of the current status of the research activities, topics that require further research studies are discussed.

Desalination of oil-contaminated saline water using membrane distillation requires hydrophobic membranes with underwater superoleophobic surfaces. For designing such membranes, the chemistry and morphology of the interfacial domains in contact with the contaminated water need to be adjusted such that a stable water layer, adhering to the surface, prevents oil droplets from wetting the membrane. In this article, we present an approach that relies on the controlled functionalization of the surface of polyvinylidene fluoride (PVDF) membranes; we adjust the surface topography of the membranes and introduce chemical heterogeneity to them. We show that the morphology of the PVDF surface can be altered by adjusting the composition of the nonsolvent bath used for the phase inversion process. Also, we render the surface of the membranes hydrophilic by using an alkaline chemical bath solution. The membrane morphology and effectiveness of our chemical treatment were confirmed by atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), Fourier-transformed infrared spectroscopy (FTIR), and zeta potential measurements. A stable underwater contact angle, higher than 150°, was observed for both canola oil (ρ ≈ 0.913 g cm −3 , γ ≈ 31.5 mN m −1 ) and hexane (ρ ≈ 0.655 g cm −3 , γ ≈ 18 mN m −1 ). We evaluated the performance of both pristine and functionalized membranes in a laboratory-scale direct contact membrane distillation (DCMD) setup and desalinated a saline solution contaminated with 500 ppm canola oil. Our results show that oil does not wet the functionalized membrane during the desalination process. The average permeate flux and salt rejection values for the functionalized membranes were 45 ± 5 Lm -2 h -1 (T feed = 70 °C, T distillate = 20 °C) and 99.99%, respectively.

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A thin-film nanocomposite (TFN) membrane was developed by integrating zwitterionic polymeric nanoparticles into the active layer of the membranes. High surface area zwitterionic polymeric nanoparticles (370 m 2 /g) were developed through distillation−precipitation polymerization (DPP). Sodium 4-vinylbenzenesulfonate (SVBS) was used as the monomer and N,N′methylenebis(acrylamide) (MBAAm) utilized as the cross-linking agent. L-cysteine (L-Cys) was tethered to these matrices through thiol−ene reaction. The assynthesized zwitterionic P(MBAAm-co-SVBS)@L-Cys nanoparticles were dispersed into the organic solution of trimesoyl chloride (TMC) to be integrated into the polyamide (PA) selective layer of thin film nanofiltration membranes. The PA layer was synthesized by interfacial polymerization through the reaction of 2% (w/ v) of piperazine (PIP) in the aqueous phase and 0.15% (w/v) of the TMC solution. The fabricated TFN membranes exhibited pure water permeability (J w ) of 11.4 L/m 2 h bar and salt rejection value of 97.6% and 16.9%, for sodium sulfate and sodium chloride, respectively. The fabricated membranes demonstrated metal ion removal efficiencies of 99.48% and 95.67% for Pb 2+ and Cd 2+ ions, respectively.