Platinum(II)-containing donor-acceptor dimesitylborane-based complexes: Synthesis, characterization, photophysical and photovoltaic properties

Abstract

• Platinum(II)-containing donor-acceptor (D-A) dimesitylborane-based complexes were synthesized. • Photophysical, electrochemical and photovoltaic properties of the complexes were investigated. • Complexes have narrow energy bandgaps and broad absorption bands. • Bulk heterojunction solar cells show the power conversion efficiency reaching 3.07%. A new series of platinum(II)-containing donor-acceptor (D-A) dimesitylborane-based complexes PT1−PT4 have been successfully synthesized in reasonable yields. The photophysical and electrochemical properties have also been investigated. Complexes PT1−PT4 have narrow energy bandgaps within 1.69−1.74 eV and broad absorption bands within 240−700 nm, which would be suitable candidates for the fabrication of devices in bulk heterojunction (BHJ) solar cells. The devices based on PT4 , which has the longest π-conjugated framework, showed the highest PCE of 3.07% among all the devices with high open-circuit voltage ( V oc ) of 0.92 V, short-circuit photocurrent density ( J sc ) of 7.95 mA cm −2 and fill factor ( FF ) of 0.42 at the optimized active layer thickness of 85 nm. These complexes illustrate the potential of solution-processible metallo-organic D-A complexes for efficient power generation in photovoltaic implementation.