Novel nanocomposite membranes based on PBI and doped‐perovskite nanoparticles as a strategy for improving PEMFC performance at high temperatures

Abstract

Summary In this work, Sr2+ dopant effects of Ba0.9Sr0.1TiO3 and La0.9Sr0.1CrO3‐δ doped‐perovskite nanoparticles on increasing proton conductivity, fuel cell performance, and mechanical and thermal stability of polybenzimidazole‐based nanocomposite membranes were studied. The Sr2+ dopant creates cation vacancies in Ba0.9Sr0.1TiO3 doped‐perovskite nanoparticles and oxygen vacancies in La0.9Sr0.1CrO3‐δ doped‐perovskite nanoparticles. The oxygen vacancies, which decrease columbic repulsion between protons and positive ions, have a more important role than the cation vacancies. They provide high surface area and high interfacial interaction between La0.9Sr0.1CrO3‐δ doped‐perovskite nanoparticles, phosphoric acid, and polybenzimidazole for proton transfer and increase the proton conductivity of the nanocomposite membranes. In addition, the results of relative humidity effects showed that the ordered arrangement of oxygen vacancies of the La0.9Sr0.1CrO3‐δ doped‐perovskite nanoparticles creates a specific pathway in the nanocomposite membranes for increasing proton transfer in the presence of relative humidity. Furtheremore, at phosphoric acid doping level of 13 mol phosphoric acid per monomer unit, proton conductivity of the nanocomposite membranes containing 8 wt.% La0.9Sr0.1CrO3‐δ doped‐perovskite nanoparticles was obtained as 126 mS cm‐1 at 180°C and 6% relative humidity. The nanocomposite membrane showed the best performance and the power density of 0.62 W cm‐2 at 180°C and 0.5 V.

First‐principles study ofCs2Ti1−xMxBr6(M = Pb, Sn) and numerical simulation of the solar cells based onCs2Ti0.25Sn0.75Br6perovskite

“…Therefore considering the defect density value of 10 13 cm −3 , the simulated results suggest that the highest efficiency that can be achieved with the planar perovskite solar cell configuration FTO/c-TiO 2 (20 nm)/Cs 2 Ti 0.25 Sn 0.75 Br 6 (600 nm)/Cu 2 O (200 nm)/Au is 22.13%. These results are based on a lead-free environmental friendly composition Cs 2 Ti 0.25 Sn 0.75 Br 6 and these results could be perceived as significant information for the development of future eco-friendly perovskite solar cells 9,46 as the perovskite solar cells without 'Pb' as the 'B' metal cation in perovskite matrix were unable to achieve such high efficiencies.…”

“…Many attempts have been made to design efficient perovskite solar absorbers, however, the challenges such as toxicity, instability against moisture and temperature, unsuitable indirect band gap, and so on still prevail 1‐8 . Previous studies have reported environmentally benign perovskites 9,10 but the power conversion efficiency (PCE) remains low or suffers rapid degradation over time 11‐13 . The fully inorganic vacancy ordered caesium titanium‐based perovskite Cs 2 TiBr 6 reportedly have shown stability against heat and moisture with promising efficiency of ~3.3% 14 .…”

Synthesis and characterization of poly 2‐ N ‐acrylamido‐2‐methyl−1‐propane sulfonic acid functionalized graphene oxide embedded electrolyte membrane using DOE for PEMFC

“…However, Figure 5B shows the main effect plot for residual percentage. It reveals that by increasing the amount of CPVC, the oxidative stability of membranes decreases as by increasing percentage of CPVC hydrocarbon backbone increases which is prone to the attack of free radicals such as hydroperoxy ( ● OOH) and hydroxy ( ● OH) radicals 57,58 . However, by increasing the amount of PAMPS‐mGO, the oxidative stability of membrane increases due to the stable nature of GO sheets.…”

“…It reveals that by increasing the amount of CPVC, the oxidative stability of membranes decreases as by increasing percentage of CPVC hydrocarbon backbone increases which is prone to the attack of free radicals such as hydroperoxy ( • OOH) and hydroxy ( • OH) radicals. 57,58 However, by increasing the amount of PAMPS-mGO, the oxidative stability of membrane increases due to the stable nature of GO sheets. Furthermore, the oxygen-containing functionalities of GO offer extensive hydrogen bonding with the polymeric membrane and lead to compact membrane.…”

Metal Organic Frameworks Modified Proton Exchange Membranes for Fuel Cells

“…At present, the most widely used PEMs is the Nafion membrane of DuPont Company. However, due to the high price of Nafion membrane, scientists are actively seeking alternative materials to Nafion membrane, such as sulfonated poly (aryl ether)s (Hooshyari et al, 2020 ). The introduction of sulfonic acid group can obviously improve the conductivity of membranes.…”