Isolation of monomeric copper(II) phenolate selenoether complexes using chelating orthobisphenylselenide-phenolate ligands and their electrocatalytic hydrogen gas evolution activity.

A series of novel copper(II) phenolate selenoether complexes have been synthesized and structurally characterized for the first time from copper(I) phenanthroline and various substituted ortho-bisphenylselenide- phenol chelating ligands. The synthesized complexes exhibit Jahn--Teller distortion in their geometry and varied from distorted square planar to distorted octahedral by varying the substituent in the bis-selenophenolate ligand. The synthesized complexes electrocatalyze the hydrogen evolution reaction (HER) with a faradaic efficiency of up to 89%, and it was observed that the distorted square pyramidal geometry is the optimum geometry for the maximum efficiency of these copper complexes. [ABSTRACT FROM AUTHOR]