Recent Advances in Metal Triplet Emitters with d6, d8, and d10 Electronic Configurations

Basic research on the photophysical and photochemical properties of metal triplet emitters has been fueled by their practical applications in diverse areas, including bioimaging, photocatalysis, and organic light-emitting diodes (OLEDs). In addition to the extensively investigated Ru(II), Ir(III), and Pt(II) complexes, a wide range of luminescent Pd(II), Au(III)/Au(I), Re(I), Cu(I), W(VI)/W(0), and Mo(0) complexes have recently been revealed via the judicious choice of ligands to exhibit unique emissive excited states with a large range of radiative and nonradiative decay rate constants. Here, we provide an account of the design strategies of and recent advances on metal triplet emitters. Questions regarding future research in this field are presented.