Ladder-type high gap conjugated polymers based on indacenodithieno[3,2-b]thiophene and bithiazole for organic photovoltaics

Two push-pull type conjugated polymers - PIDTT−BTz and PIDTT−DTBTz, based on the ladder-type donor unit indacenodithieno[3,2-b]thiophene (IDTT) and bithiazole (BTz) as acceptor component - are designed and synthesized for photovoltaic applications. The polymers exhibit relatively high optical gaps of ~2.0 eV with strong absorption in the range of 400–600 nm, rendering them of particular interest for the harvesting of indoor light and/or multijunction devices. Electrochemical investigations indicate a lower highest occupied molecular orbital energy level (−5.44 eV) for PIDTT−BTz as compared to PIDTT−DTBTz (−5.36 eV), enabling to achieve a higher open-circuit voltage. Under solar illumination, the best power conversion efficiency (5.1%) is achieved for the combination PIDTT−DTBTz:PC71BM (compared to 4.6% for PIDTT−BTz:PC71BM).

Jaar van publicatie:2019

Trefwoorden:Bithiazole, High gap polymers, Indacenodithieno[3,2-b]thiophene, Indoor photovoltaics, Organic solar cells

CSS-citation score:1

Toegankelijkheid:Closed