Highly efficient photocrosslinking of ultrahigh work function conjugated polymers using bis(fluorophenyl azide) additives

02/12/2019. Self-compensated hole-doped conjugated polyelectrolytes with ultrahigh work functions have been demonstrated to be high performance hole collection/injection layers in organic solar cells and diodes in our earlier work. The ability to crosslink such layers can further increase flexibility in device processing and improve stability. However, it is possible to achieve efficient crosslinking of ultrahigh work function doped polymers without degrading its properties? ONDL PhD student Desmond TEO and his team found out that not only is their recently developed bis(fluorophenyl azide) photocrosslinker i-line compatible, it can also achieve almost 100% photocrosslinking efficiency with a model polyelectrolyte while retaining (in fact, exceeding) the high performance in device implementation. The team has demonstrated a large 12% relative increase in power conversion efficiency of a modern organic solar cell by simply photocrosslinking the polyelectrolyte hole collection layer.DOI: 10.1021/acsami.9b12503