Applications of porphyrins in emerging energy conversion technologies

Porphyrins are composed of four pyrrolic subunits interconnected via methine bridges to form fully conjugated 18 π electron-containing aromatic macrocycles. This macrocyclic aromatic compound has various interesting optical, electrical and physicochemical properties. Because of their unique features, it is possible for the porphyrin derivatives to reversibly convert photo, electrical and chemical energy, which lead them to be the key materials in energy conversion systems. In photovoltaics, the porphyrin derivatives generate electrical energy via absorbing light energy. They also serve as photocatalyst to convert light to chemical energy. Moreover, they play a role in electrode of the energy storage systems due to their unique electrochemical redox properties. In this paper, emerging development in terms of porphyrin-based energy conversion systems will be review. This review is divided into three sections focusing on porphyrin-based energy conversion technologies for (i) photovoltaics, (ii) photocatalysts and (iii) energy storage systems, respectively.