Exploring the Electrocatalytic Reduction of Water and Aqueous Nitrite with Water-Soluble, Earth Abundant Metal Complexes and Attempts at Developing an "Electrophotocatalytic" Method for the Reduction of CO₂

Abstract

The importance of addressing environmental issues such as lowering the emission of greenhouse gases, preventing eutrophication of aquatic life due to high concetrations of nitrogen oxyanions, and producing sustainable energy is at an all-time high. With a concentration on employing earth abundant metals, a Mn(I) complex was synthesized with an integrated photocatalyst in an attempt at developing a new electrophotocatalytic system. Additionally, a Ni(II) pincer complex was synthesized and structurally and computationally characterized as well as observed to perform electrocatalytic hydrogen generation in water. Lastly, with inspiration from the Ni(II) pincer complex, two macrocyclic complexes, one with a Ni(II) center and the other with a Co(II) center, were structurally characterized and observed to electrocatalytically reduce aqueous nitrite at neutral pH. DFT calculations were also performed to elucidate the nitrite reduction reaction mechanism.