Novel photosensitizer paradigms featuring Earth-abundant metals are highly sought after due to their low cost, low toxicity, and abundance. In this study, we pursue a bimetallic paradigm for an Earth-abundant-metal photosensitizer design. We describe the synthesis, structure, and photophysical properties of a series of dicopper(I) complexes supported by a naphthyridine diimine ligand. Time-resolved spectroscopic and computational studies reveal excited states with (MM)LCT character formed at absorptions in the visible range. The excited-state lifetimes of these complexes are slightly perturbed by the anionic counterions bound to copper.

The use of electrolyte additives at millimolar loadings to control the surface chemistry of lithium metal anodes (LMAs) is a leading strategy to improve lithium metal batteries and promote electrosynt...