Supramolecular self-assembly and photovoltaic property of soluble fluorogallium phthalocyanine

Abstract

Within the present work, two soluble phthalocyanine compounds, fluorogallium tetra-tert-butylphthalocyanine (ttbPcGaF) and its precursor hydroxygallium tetra-tert-butylphthalocyanine (ttbPcGaOH) were successfully synthesized. ttbPcGaF had a considerably stronger ability than that of ttbPcGaOH to self-organize into well-ordered one-dimensional (1D) supramolecular polymers in solid state by solution-coating technique. The photovoltaic properties of ttbPcGaF and ttbPcGaOH as electron donor materials in solution-processed bulk heterojunction (BHJ) organic solar cells (OSCs) were investigated. Due to the retention of the self-assembly property of ttbPcGaF and nanoscale phase separation in the ttbPcGaF : PC₆₁BM blend film, the ttbPcGaF-based BHJ OSC provided a profoundly improved power conversion efficiency (PCE) of 0.41%, as compared with a low PCE of 0.03% afforded by ttbPcGaOH.