Palladium(II) and Platinum(II) Porphyrin Donors for Organic Photovoltaics

Three new A-π-D-π-A structural porphyrin-based donors, C19-H2P, C19-PdP, and C19-PtP, are designed synthesized, with porphyrin (D) moieties equipped no metal, palladium (Pd), platinum (Pt) as the core, respectively, end-capped electron-deficient 3-ethylrhodanine (A) via a π-bridge of phenylene ethynylene linker. C19-PdP C19-PtP exhibit low-lying highest occupied molecular orbital levels than C19-H2P. The three donors show highly intensified broad absorptions at ca. 400–530 nm (Soret bands) 550–800 (Q-bands) an absorption valley 540 nm. Using PC71BM electron acceptor, devices based on achieve power conversion efficiencies (PCEs) 8.09 7.31% under 1 Sun, whereas C19-H2P device, that has very low PCE 2.51%. Furthermore, 300 lux LED source, deliver promising PCEs 16.54 16.74%, respectively. improved performance C19-PdP- C19-PtP-based is mainly due to more efficient charge collection, faster transport, suppressed recombination behavior, smoother surface morphology. These findings pave way for development metalloporphyrin-based organic solar cells using simple engineering.