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Quantum dots are semiconductor nanoparticles containing a range of materials with a core-shell structure. They receive discernible attention in today's world due to their potential applications, from energy storage devices to medical applications. Nevertheless, there are many approaches to their synthesis and stability routes. This review focuses on two approaches for the synthesis of quantum dots, namely surface functionalization and quantum dot doping. In addition, their stability routes were discussed, such as the intermediate shell approach, alloyed core/shell approach, shell thickness approach, ligand design approach, and over-coating approach. The review concludes by addressing the recent progress of quantum dots applications, notably in photocatalysis for different applications, such as cathode, anode, and membranes for fuel cell applications, solar cells, sensors, and various energy storage devices applications. • QDs are characterized by their tunable size, composition, and fluorescence features. • Functionalization and doping of QDs are the main remarkable achievements in synthesis. • The stability of QDs can be enhanced by following the core-shell structure. • QDs can be stabilized by the intermediate shell approach, alloyed core/shell approach, and overcoating approach. [ABSTRACT FROM AUTHOR]

With the growing demand for green technologies, hydrogen energy devices, such as Proton Exchange Membrane (PEM) fuel cells and water electrolysers, have received accelerated developments. However, the materials and manufacturing cost of these technologies are still relatively expensive which impedes their widespread commercialization. Additive Manufacturing (AM), commonly termed 3D Printing (3DP), with its advanced capabilities, could be a potential pathway to solve the fabrication challenges of PEM parts. Herein, in this paper, the research studies on the novel AM fabrication methods of PEM components are thoroughly reviewed and analysed. The key performance properties, such as corrosion and hydrogen embrittlement resistance, of the additively manufactured materials in the PEM working environment are discussed to emphasise their reliability for the PEM systems. Additionally, the major challenges and required future developments of AM technologies to unlock their full potential for PEM fabrication are identified. This paper provides insights from the latest research developments on the significance of advanced manufacturing technologies in developing sustainable energy systems to address the global energy challenges and climate change effects. • The AM technologies relevant to PEM fabrication are reviewed. • Corrosion performance of AM materials in the PEM working environment is presented. • The challenges and prospects of AM for PEM fabrication are discussed. • AM has the potential to revolutionize the fabrication of PEM systems. [ABSTRACT FROM AUTHOR]

This paper reviews the common existing designs of flow plates of fuel cells and suggests modifications to some of them to help reduce the pressure drop in the flow channels. Pressure drop is one of the factors that influence the overall performance of the cell both directly and indirectly through interaction with other factors including water management in the cell. The work uses computational fluid dynamics (CFD) to examine different design and study the effect of varying the flow rate (i.e. velocity) on the pressure drop for each of the designs modelled. Again, the designs are optimized by changing different parameters using ANSYS CFX. Results showing the effects of the modifications on pressure drop in the various plates are presented in this paper. From the study of the various designs, a conclusion was drawn that a modification of fuel cell designs in existence using a system similar to the diesel injection system design approach reduced the pressure drop in the fuel cell as shown by the simulation results. This reduction in pressure drop will contribute to the improvement of performance but it must be stressed that other factors also contribute to the overall performance of the cell and reduction in pressure drop alone is not a guarantee of better performance of a certain fuel cell design. [ABSTRACT FROM AUTHOR]