To meet growing energy demands worldwide, both public and private entities have identified the production of hydrogen through environmentally conscious and economically viable means as a key bottleneck to the wide scale implementation of hydrogen fuel cells. One such promising route, electrolysis, requires the development of reliable catalysts to drive the sluggish and energy intensive oxygen evolution reaction (OER) and to improve the overall efficiency of the electrolysis process. Tunnel manganese oxides are attractive candidates for OER catalysis applications because of their high electrochemical activity and natural abundance, which make them fiscally appealing. Moreover, tunnel manganese oxide's open crystal structures allow for facile chemical manipulations of the cationic and anionic sublattices which in turn provides methods to control specific material attributes, such as oxidation state and vacancy concentration. In this work, acid leaching and transition metal doping approaches were investigated separately and sequentially to provide insights into how tunnel manganese oxides can be engineered on the atomic and micron scales to control OER activity. |