Water is an absolute necessity for life as we know it. It provides a useful medium in which chemical reactions take place that allowed for the development of single cellular organisms. When combined with the evolutionary accident that was pho- tosynthesis, water became not only a useful medium chemical reactions, but also a ready feedstock for the storage of chemical energy.
The potential to use water as the feedstock for energy storage is not simply of interest on the cellular level. One of the earliest popular references to the use of water for energy storage was by the 19th-century science fiction writer Jules Verne
in The Mysterious Island in 1874, and ever since then idea has tantalized scientists and engineers. The benefits of a energy system based on the conversion of water into a fuel and then back to water are self-evident and as a result the topic has been the focus considerable interest over the past 144 years. In that time, however, the energy required to produce hydrogen at the scale necessary has not been available.
The technologies required to enable the actual transition from a carbon-based energy dependence to a renewable energy system are only recently coming on-line. The greatest driver in this transition is the realization that continued reliance on fossil energy has placed us at the cusp of environmental catastrophe. This, in turn, has driven the development of renewable energy generation technologies. Gains in renewable energy capacity have exposed the inherent dissonance between when renewable energy is available and when energy in general in demand, in order to bridge that gap energy storage technologies need to be developed and deployed on a truly massive scale.
The scale of the energy storage problem necessitates strategies that utilize abun- dant materials for components of an energy storage system. This allows us to fall back on some microbial wisdom and refocus on water as an energy storage feedstock. Converting water into hydrogen and oxygen and then storing the hy-
drogen for later use as a fuel can be achieved by three means: thermochemical, photoelectrochemical, and electrochemical. The most technologically feasible and widely applicable method of hydrogen generation is via electrochemical means. Of the electrochemical devices for hydrogen production, the most efficient rely on the use of platinum group metals (PGM) as catalysts, adding significant cost to their manufacture and limiting the scale at which they can be deployed. This points to the need to develop non-PGM catalysts for use in water-splitting devices.
This dissertation focuses on two main subjects. First is the synthesis and physical characterization of first-row transition metal-based materials deposited in meso- porous substrates and their electrochemical performance as catalysts in water- splitting reactions. Second is the field’s current understanding of correlation be- tween the presence of iron and catalyst efficacy with the author’s own work demonstrating the superior performance of iron based catalysts. It is the hope of the author that reader will gain knowledge of the methods of deposition in porous carbon substrates and an understanding of electrochemical characterization of catalyst performance as it applies to water-splitting reactions.