Solid oxide electrolyzer cells

Production of renewable hydrogen with zero net emission of greenhouse gases plays an important role in the development of clean and sustainable hydrogen economy. Renewable hydrogen can be produced by using solar energy directly in thermochemical water splitting to dissociate water into hydrogen and oxygen. However, a recent study has shown that in terms of potential economic benefit, thermochemical water splitting is not as attractive as water electrolysis (Graf 2008). Photocatalysis is another potential method for production of renewable hydrogen by direct use of solar radiation to reduce water. For the present development of the technology, the photocatalytic efficiency is too low to be economically competitive (Ni et al. 2007a). More research and development are needed to enhance the catalysts and reactor designs.