Small Molecule Near-Infrared Boron Dipyrromethene Donors for Organic Tandem Solar Cells

Three furan fused boron dipyrromethenes
(BODIPYs) with a CF3 group on the meso-carbon are synthesized
as near-infrared absorbing materials for vacuum processable organic
solar cells. The best single junction device reaches a short-circuit
current (jsc) of 13.3 mA cm–2 and a power conversion efficiency (PCE) of 6.1%. These values are
highly promising for an electron donor material with an absorption
onset beyond 900 nm. In a tandem solar cell comprising a NIR BODIPY
subcell and a matching “green” absorber subcell, complementary
absorption is achieved, resulting in PCE of ∼10%.