Transition metal complexes have been widely used as light-emitting and photon-absorbing materials in optoelectronic devices with diverse applications.While these complexes have been intensively studied in the field of organic light-emitting devices (OLEDs) due to their inherently high phosphorescence quantum yields (Φ) ,they are rarely employed in the fabrication of organic solar cells (OSCs) with reported examples showing poor photovoltaic responses with unexpectedly low power conversion efficiency (PCE) of ≤ 2.9％for most of the vacuum-deposited devices or ≤ 5.0％for solution-processed devices in the literature.