The photostability of such heteroleptic Ir(III) complexes can be improved with the introduction of more robust bidentate ligands, such as those reported by Che and co-workers who employed a series of bis(Nheterocyclic carbene) (NHC) ligands as ancillary ligands in complexes of the type [Ir(C^N)2(bis-NHC)] + (Figure ). One of the investigated PCs, 4 Me b, underwent only a 5% structural degradation after irradiation with blue LEDs (12 W, λexc = 462 nm) for 120 hours, while under the same conditions Ru(bpy)3Cl2, fac-Ir(ppy)3 and [(dF[CF3]ppy)2Ir(dtbbpy)]PF6 completely photodegraded after 10 hours of irradiation. This family of cationic complexes showed reasonably balanced excited-state redox potentials (E*ox = -1.26 to -1.70 and E*red = 0.44 to 1.03 V vs. SCE in MeCN) and were capable of dehalogenating aryl bromides and iodides to facilitate a reductive cyclization cascade. Similarly, Lai Fung-Chan and co-workers employed a series of substituted pyridylidene NHC ancillary ligands to form complexes of the type [Ir(ppy)2(py^NHC)] + (Figure ) and [Ir(ppz)2(py^NHC)] + complexes (where ppz = 1-phenylpyrazolo). Like the work by Che and co-workers, the complexes exhibited balanced though moderately reducing/oxidizing excited-state redox potentials (E*ox = -0.99 to -1.54 and E*red = 0.87 to 1.09 V vs. SCE in MeCN) and were employed in both an oxidative and reductive quenching reaction.