Alkaline Fuel Cells, Theory and Applications

Tuning Stainless Steel Oxide Layers through Potential Cycling─AEM Water Electrolysis Free of Critical Raw Materials

“…Moreover, these potentials are an approximation of the potential region at which the EIS spectra intercept the x -axis for the second time. The distance between the first and second x -axis intercepts denotes the charge transfer resistance R ct , that is, the resistance associated with a faradaic process. , EIS was utilized to ascertain the series resistance R s , where this value was later employed to correct LSV curves for ohmic resistance (100%). Several open-circuit EIS spectra were collected, where R s was determined as the mean of these spectra with the associated uncertainty.…”

“…Increasing emphasis on renewable energy sources has accelerated the development of wind and photovoltaic power, where a combination of their intermittent nature and increasing presence has exponentially increased the importance of energy storage. , Electrochemical energy storage devices, such as batteries and hydrogen-producing water electrolyzers, are favorable candidates for storing surplus energy until a shortage arises. Alkaline water electrolysis (AWE) has been the dominant method for the production of green hydrogen for more than a century, whereas the acidic proton exchange membrane water electrolyzer (PEMWE) has only recently begun to show any impact on an industrial scale .…”

“…Compared to traditional AWEs, AEMWEs produce higher current densities while boasting reduced gas crossover and a higher purity of hydrogen, while requiring a significantly less corrosive electrolyte (1.0 M ≪ 8.0 M KOH). , Moreover, inexpensive metals such as iron and nickel can easily catalyze both the alkaline OER and HER. ,, The infamous anodic OER has frequently been the focus of many investigations due to the complexity arising from a four-electron reaction, which conspires to lower its exchange current density several orders of magnitude below the cathodic HER. , Spinels, perovskites, and alloys that comprise abundant elements (Fe and Ni) have produced respectable results as OER catalysts, , although aspects related to stability and scalability remain challenging. , Creating an active layer by electrochemically modifying a surface has also been attempted on numerous occasions, usually resulting in a NiFeO x H y layer active toward the OER. ,− This has most commonly been performed by performing chronopotentiometry on various surfaces in alkaline solutions. − …”

How Acid Washing Nickel Foam Substrates Improves the Efficiency of the Alkaline Hydrogen Evolution Reaction

“…The ongoing renewable energy transition includes new energy carriers such as hydrogen [1][2][3][4], where production through water electrolysis yields green hydrogen. Key to this process is the hydrogen evolution reaction (HER), which is one of the two half-cell reactions in water electrolysis [5].…”

“…Key to this process is the hydrogen evolution reaction (HER), which is one of the two half-cell reactions in water electrolysis [5]. The advent of the novel anion exchange membrane (AEM) [1][2][3][4] has caused a shift within water electrolysis creating a greater emphasis on alkaline water electrolysis utilising AEM technology. The alkaline HER is currently under profound scrutiny, as there is considerable difficulty in finding stable catalyst materials capable of replacing platinum group metals (PGMs) [5].…”