Single-Layer Electroluminescent Devices and Photoinduced Hydrogen Production from an Ionic Iridium(III) Complex

We report the electronic structure and diverse applications of a highly luminescent ionic transition metal complex, [Ir(dF(CF 3 )ppy) 2 (dtbbpy)](PF 6 ) (where dF(CF 3 )ppy = 2-(2,4-difluorophenyl)-5-trifluoromethylpyridine and dtbbpy = 4,4‘-di- tert -butyl-2,2‘-dipyridyl). The large HOMO−LUMO gap (Δ E = 3.06 V) enabled high-energy electroluminescence from the complex. Single-layer devices were fabricated and found to emit blue-green light (500 nm). The strong reducing strength of the excited state ( E * ox = 1.21 V) enabled effective catalysis of the photoinduced reduction of H 2 O to H 2 . It was found that the relative quantum yield of hydrogen was over an order of magnitude improved from the standard photosensitizer Ru(dmphen) 3 2+ (dmphen = 4,7-dimethyl-1,10-phenanthroline).