Introduction to the Water Splitting Reaction

This chapter will cover the most important aspects concerning the water splitting reaction by providing an overall description of the main solutions, as reported in the literature, addressing the improvement of the efficiency of solar driven hydrogen production. The natural water splitting system will be considered as a starting point, in order to gain a better understanding of the main challenges that material scientists are facing towards the development of novel catalysts of water oxidation, mainly. The attention will focus on the water oxidation half-reaction, since it is the most complex and demanding process from both the kinetic and thermodynamic points of view. In addition, some general aspects of the photocatalytic water splitting and the principal semiconductors studied for such process will be reviewed.