Direct methanol fuel cell (DMFC) with noble metals based anode and cathode is a promising energy generator to portable power devices. However, the deterioration of catalyst performance suffered by CO poisoning, crossover of fuel from anode to cathode, and higher economical cost of such devices hinder their commercialization. Herein, all of the above issues have been neutralized and crossed the huge hump of faced challenges. Highly efficient, durable, and surfactant-free catalyst with ultralow Pt3Pd1 loadings supported on CeO2/C was synthesized. The ex-situ and in situ spectroelectrochemical techniques such as, CV, in situ FTIR, and online DEMS studies confirm the highly efficient activity of catalyst toward electro-oxidation of methanol. In addition, the critical and detailed analysis of RDE results prove the superiority of the present material for electro-reduction of oxygen along a cathode side. The as-synthesized catalyst has proven itself as a better substitute for commercial Pt/C catalyst, with enhanced and durable performance as anode and cathode material for DMFCs. The obtained remarkable performance of catalysts can be attributed to the accumulative effects of PtPd bimetallic NPs and the enhanced synergistic factors of CeO2 in a hybrid material.

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This manuscript describes the synthesis of dimethylethanolamine (DMEA)-grafted anion exchange membrane (AEM) by incorporating dimethylethanolamine as ion-exchange content into the polymer matrix via the solution casting method. The synthesis of the DMEA-grafted AEM was demonstrated by Fourier transform infrared (FTIR) spectroscopy. The prepared DMEA-grafted AEM exhibited higher thermal stability, homogeneous morphology, water uptake (WR) of 115%, and an ion exchange capacity (IEC) of 2.70 meq/g. It was used for the adsorptive removal of methyl orange (MO) from an aqueous solution via batch processing. The effect of several operating factors, including contact time, membrane dosage, initial concentration of aqueous dye solution, and temperature on the percentage discharge of MO and adsorption capacity, was evaluated. Experimental data for adsorption of MO onto the DMEA-grafted AEM was analyzed with two parameter and three parameter nonlinear adsorption isotherm models but fitted best using a nonlinear Freundlich isotherm. Adsorption kinetics were studied by using several models, and attained results showed that experimental data fitted well to pseudo-second-order kinetics. A thermodynamic study showed that adsorption of MO onto the prepared DMEA-grafted AEM was an endothermic process. Moreover, it was a feasible and spontaneous process.

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 (WR) 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 Co0.1Al0.03Fe0.17O0.4 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 Co0.1Al0.03Fe0.17O0.4.