Four spiro[fluorene-9,9′-xanthene] (SFX)-based hole transporting materials (HTMs) functionalized with four-armed arylamine moieties located at different positions are designed and synthesized. These compounds exhibit highest occupied molecular orbital (HOMO) energy levels of -4.9 to -5.1 eV and a hole mobility of 2.2 to 15 × 10-5 cm2 V-1 s-1 after doping. Perovskite solar cells (PSCs) based on a methylammonium lead iodide (MAPbI3) active layer using one of these HTMs (mp-SFX-2PA) exhibit power conversion efficiencies (PCEs) of up to 16.8%, which is higher than that of the control devices based on benchmark spiro-OMeTAD under the same conditions (15.5%). PSCs based on mp-SFX-2PA exhibit better stability (retain 90% of their initial PCEs after 2000 h storage in an ambient atmosphere) than the control devices based on spiro-OMeTAD (retain only 28% of their initial PCEs). mp-SFX-2PA based devices employing a mixed formamidinium lead iodide (FAPbI3)/methylammonium lead bromine (MAPbBr3) perovskite layer exhibit an improved PCE of 17.7%. The effects of arylamines and their location positions on device performance are discussed.
|Number of pages||11|
|Journal||Materials Chemistry Frontiers|
|Publication status||Published - Jan 2017|
ASJC Scopus subject areas
- Materials Science(all)
- Materials Chemistry