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Membrane-less fuel cells are a promising power source for portable applications that enable the solving of membrane-related issues, such as water management and high cost, in conventional fuel cells. Apparently, research on this system uses a single electrolyte. This study focused on enhancing the performance of membrane-less fuel cells by introducing multiple reactants that are dual electrolytes with hydrogen peroxide (H2O2) and oxygen as oxidants in membrane-less direct methanol fuel cells (DMFC). The conditions tested for the system are (a) acidic, (b) alkaline, (c) dual medium with oxygen as an oxidant, and (d) dual medium and dual oxygen and hydrogen peroxide as an oxidant. Additionally, the effect of fuel utilization on different electrolyte and fuel concentrations was also studied. It was found that the fuel utilization decreases dramatically with the increasing of the fuel concentration, but it improved with the increasing of the electrolyte concentration until 2M. The performance of the dual oxidants in dual-electrolyte membrane-less DMFCs was 15.5 mW cm−2 of the power density achieved before optimization. Later, the system was optimized, and the power density increased to 30 mW cm−2. Finally, this work presented the stability of the cell using the suggested parameters from the optimization process. This study indicated that the performance of the membrane-less DMFC increased for dual electrolytes with mixed oxygen and hydrogen peroxide as oxidants compared to a single electrolyte.

In the past two decades, a considerable amount of research has focused on digital games as part of media education. Digital game-based learning (DGBL) is identified as a potential pedagogical approach to enhance learning in the digital era. In light of the increased number of academic articles on educational games, this study considers the development and the factors that influence learning performance among children by providing a thematic review of the literature available on DGBL. Findings show that despite following developmental standard procedures, a distinct perspective between the game designer and the educator is essential. Three major approaches have been identified, namely the learner-centered, the game-centered and the model approaches. Learning processes that use digital games show empirically positive results as well as the great influence in terms of intrinsic motivation, game features and overall learning experience.