Abstract In this account, the discovery of the AZaphthalocyanine Unimolecular Layer (AZUL) catalyst, in which metal azaphthalocyanines are molecularly adsorbed on carbon, is summarized as a promising alternative to rare-metal catalysts. Also, its broad applicability to a wide range of electrochemical reactions and its implementation in practical energy devices is highlighted. Furthermore, the molecular adsorption concept is not limited to electrocatalysis but can be extended to other functional applications, such as enhancing the capacitance of supercapacitors. In addition, by combining AZUL catalysts with a recently developed electrolysis system employing regenerative redox mediators, both the overpotential required for electrolysis and the charge–discharge overpotential of zinc–air batteries can be dramatically reduced. Finally, we discuss future prospects and potential directions for the further development of this emerging catalyst platform and its associated energy technologies.
Hiroshi Yabu (Fri,) studied this question.