Opto(electrical) properties of triphenylamine-based polyazomethine and its blend with [6,6]-phenyl C61 butyric acid methyl ester

Polyazomethine (OFBF-TPA) based on triphenylamine (TPA) and octafluorobiphenyl (OFBF) moieties was tested as donor–acceptor (D-A) for bulk heterojunction polymeric solar cells. The temperatures of 5% weight loss (T5%) of the polyazomethine range from 323 to 328°C, depending on the gas used (air and nitrogen). The conductivity of OFBF-TPA was approximately 10−10 S/cm for not annealed sample and at about 10−6 S/cm for the ones annealed at room temperature, as determined by impedance spectroscopy. Surface of the polymer and mixture polymer–[6,6]-phenyl C61 butyric acid methyl ester (PCBM) was smooth with the Rms value in the range 0.58–1.95 nm as was detected by the atomic force microscopy (AFM) technique. UV-vis spectrum of the mixture OFBF-TPA-PCBM exhibited higher absorption intensity than the UV-vis spectrum of OFBF-TPA lacking PCBM. The thin solid film of OFBF-TPA and OFBF-TPA-PCBM showed one main absorption band with a maximum peak at 414 and 411 nm, respectively. For the mixture OFBF-TPA-PCBM, the sec...