Electrochemical water splitting has emerged as a pivotal technology for green hydrogen production, offering a viable pathway toward a sustainable energy future. Among various electrolysis systems, Anion exchange membrane water electrolysis is particularly noteworthy as a cost-effective solution capable of operating under the fluctuating power inputs typical of renewable energy sources. However, the overall efficiency of water splitting is fundamentally limited by the oxygen evolution reaction, which exhibits sluggish kinetics compared to the hydrogen evolution reaction. While IrO₂ and RuO₂ serve as current benchmarks, their scarcity and high cost necessitate the development of earth-abundant alternatives. This review provides a comprehensive overview of fundamental OER mechanisms including the adsorbate evolution mechanism, lattice oxygen mechanism, and oxide path mechanism while highlighting how new pathways can circumvent traditional scaling relations. We discuss recent advancements in transition metal-based electrocatalysts, encompassing oxides, hydroxides, chalcogenides, phosphides, nitrides, and carbides, with a focus on innovative design strategies such as defect engineering, heteroatom doping, and heterostructure construction. This paper concludes by addressing current challenges and offering perspectives on future directions for the development of highly efficient and economically viable oxygen evolution electrocatalysts for large-scale applications.

Thermal and electrical conductivities of the natural, artificial, and expandable graphites were analyzed after treatment in NaOH aqueous solution. In order to investigate the elimination of the oxidized groups and impurities on the graphite surfaces after NaOH treatment, the graphite samples were structurally characterized by using XRD, XPS, Raman, FE-SEM. The thermal and electrical conductivities of the graphite samples were significantly improved after NaOH treatment. These results were caused by the structural rehabiliation.

We investigated the variation of anion exchange membrane of hydrogen generator of alkaline electrolysis. We detected the variation of elements and change of anion exchange membrane using EDS and FE-SEM. We detected two different sites of membrane because of different structure of membrane. Sp2 shows that the distribution ratio of C, 0, Al is 98% very higher than Sp2 of 78%. Especially, the main elements of STS316 which is P. S. Fe, Ni were more detected at Sp2 than Sp,. We think that this result depends on the structure of membrane. This also affect the resistance, lifetime of membrane and decrease the efficiency of hydrogen production. We hope that this article is a foundation of developing of hydrogen production technology.

In this paper, We studied the change of surface and variation of elements on both electrodes of hydrogen generator of alkaline electrolysis in use of FE-SEM and SIMS. We used the stainless steel 316(6(X) p m) as electrode in condition of 25%KOH, 60℃ Temperature. The results show that the intensity of elements (C, Si, P. S. Ti, Cr, Mn, Fe, Ni, Mo) of Positive Electrode are decreased as much as about 101 than the original electrode. Thickness of Positive Electrode is decreased about 40 pin after chemical reaction. The negative electrode, however, shows a slight variation in the intensity of elements (C, Si, P. Fe, Ni, Mn, Mo) but Change of thickness and surface` shape of electrode show nothing after chemical reaction. The change in thickness and variation of Stainless Steel 316 cause the lifetime of electrode to be shorted. We also observed hydrogen. oxygen, potassium in both electrodes. Especially, The potassium is increased in proportional with depth of positive electrode. this means the concentration of alkali solutions is changed. and so we have to supply alkaline solution to generator in order to produce same quantity of hydrogen gas continuously, we hope that this study gives a foundation to develop the electrode for hydrogen generator of alkaline electrolysis.

Lead-free piezoelectric ceramic/epoxy composites with ``0-3`` connectivity were prepared by cold-pressing with a temperature controlled curing method. A ceramic powder with a composition of (Na0.51K0.47Li0.02)(Nb0.8Ta0.2)O3 was synthesized by a conventional solid state reaction route. The dielectric and piezoelectric properties of ceramic/epoxy composites were characterized as a function of the volume fraction (φ) of piezoelectric ceramics, which was varied from 70 to 95vol%. The results indicated that the piezoelectric properties of composites were significantly affected by the volume fraction of ceramics. In terms of the piezoelectric properties, specimens showed the best performance at φ= 85vol%, resulting in the piezoelectric constant d33 of 39pC/N and the figure of merit as a piezoelectric energy harvester (d33·g33) of 1.24 pm2/N.