Anion exchange membrane fuel cells (AEMFCs) are encouraging electrochemical structures for the competent and complaisant conversion of energy. Herein, the development of brominated poly(2,6-dimethyl phenylene oxide) (BPPO)-based anion exchange membranes (AEMs) with different quaternary ammonium groups for AEMFCs was reported. The successful preparation of AEMs was proved by utilizing proton nuclear magnetic resonance and Fourier transform infrared spectroscopy. They were explored in terms of water uptake (W_R), ion exchange capacity (IEC), hydration number (λ), linear swelling ratio (LSR), morphology, tensile strength (TS), and elongation at break (E_b). The alkaline stability of the prepared AEMs was assessed and compared with each other. The experimental outcomes demonstrated that the N-methylpyrrolidinium-based membrane (MPyPPO) exhibited higher alkaline stability, whereas the N-methylimidazolium-based membrane (MImPPO) showed the lowest alkaline stability among the prepared AEMs. Similarly, the hydroxide conductivity of the prepared AEMs was measured and compared with each other. The pyrrolidinium-based membrane (MPyPPO) exhibited higher hydroxide conductivity among the prepared AEMs.

In fuel cell applications, the proton exchange membrane (PEM) is the major component where the balance among dimensional stability, proton conductivity, and durability is a long-term trail. In this research, a series of blended SPEEK/SPPO membranes were designed by varying the amounts of sulfonated poly(ether ether ketone) (SPEEK) into sulfonated poly(phenylene) oxide (SPPO) for fuel cell application. Fourier transform infrared spectroscopy (FTIR) was used to confirm the successful synthesis of the blended membranes. Morphological features of the fabricated membranes were characterized by using scanning electron microscopy (SEM). Results showed that these membranes exhibited homogeneous structures. The fabricated blended membranes SPEEK/SPPO showed ion exchange capacity (IEC) of 1.23 to 2.0 mmol/g, water uptake (W_R) of 22.92 to 64.57% and membrane swelling (MS) of 7.53 to 25.49%. The proton conductivity of these blended membranes was measured at different temperature. The proton conductivity and chemical stability of the prepared membranes were compared with commercial membrane Nafion 117 (Sigma-Aldrich, St. Louis, Missouri, United States) under same experimental conditions. The proton conductivity of the fabricated membranes increased by enhancing the amount of SPPO into the membrane matrix. Moreover, the proton conductivity of the fabricated membranes was investigated as a function of temperature. Results demonstrated that these membranes are good for applications in proton exchange membrane fuel cell (PEMFC).

The present study is aimed to access the photodegradation efficiency of methylene blue dye using CoFe₂O₄ and Co_0.1Al_0.03Fe_0.17O_0.4 nanoparticles. The synthesis of spinel ferrites nanoparticles was performed by a facile sol-gel method. The synthesized nanoparticles were characterized by FTIR, XRD, SEM, EDS, Nitrogen adsorption/desorption and UV–Visible spectroscopy. The XRD studies confirmed the spinel cubic structure of ferrite. It was also found that the crystallinity increases at an annealing temperature of 800 °C. The application of these nanoparticles for methylene blue’s photocatalytic degradation was explored and also the optimization of several parameters involving dye’s concentration, amount of catalyst and pH of the solution was done. Photocatalytic degradation of methylene blue showed that at pH 11, using 200 W visible light bulb and in 120 min; 93% methylene blue dye was degraded by using 0.1 g of Co_0.1Al_0.03Fe_0.17O_0.4.

In recent years, the continuously increasing demand for wastewater treatment has increased research on perovskite-based materials with narrow band gaps. Titanium-doped calcium bismuth ferrites (CaBiFe_1−x Ti_xO₃x = 0.00–15%) were successfully synthesized using the co-precipitation method. X-Ray diffraction data and SEM micrographs revealed the phase purity and nanocrystalline nature (rhombohedral lattice) of the CaBiFe_1−x Ti_xO₃x = 0.00–15% samples. The energy band gap of the Ca-BiFO₃ nanoparticles was tuned by the substitution of Ti⁴⁺ ions in the range of 2.96–2.1 eV. The Ti⁴⁺ substituted Ca-BiFO₃ nanoparticles exhibited much higher photocatalytic performance for antibiotics (moxifloxacin) under controlled UV-visible light irradiation compared to pristine Ca-BiFO₃ nanoparticles. The high concentration of moxifloxacin in water causes environmental problems, such as antibacterial resistance in bacteria and threats to ecology. The CaBiFe_85%Ti_15%O₃ nanoparticles showed 89.16% moxifloxacin degradation after irradiation for only 60 min. The significant changes in the photocatalytic properties of the sample were due to the aliovalency of Fe³⁺ and Ti⁴⁺, and differences in ionic radii and oxygen vacancies.