title: The influence of electron injection and charge recombination kinetics on the performance of porphyrin-sensitized solar cells: effects of the 4-tert-butylpyridine additive.
abstract: The effects of the 4-tert-butylpyridine (TBP) additive in the electrolyte on photovoltaic performance of two push-pull porphyrin sensitizers (YD12 and YD12CN) were examined. Addition of TBP significantly increased the open-circuit voltage (VOC) for YD12 (from 550 to 729 mV) but it was to a lesser extent for YD12CN (from 544 to 636 mV); adding TBP also had the effect of reducing the short-circuit current density (JSC) slightly for YD12 (from 17.65 to 17.19 mA cm(-2)) but it led to a significant reduction for YD12CN (from 16.45 to 9.78 mA cm(-2)). The resulting power conversion efficiencies of the YD12 devices increase from 6.2% to 8.5% whereas those of the YD12CN devices decrease from 5.8% to 4.5%. Based on measurements of temporally resolved photoelectric transients of the devices and femtosecond fluorescence decays of thin-film samples, the poor performance of the YD12CN device in the presence of TBP can be understood as being due to the enhanced charge recombination, decreased electron injection, and a lesser extent of inhibition of the intermolecular energy transfer.
authors: Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan.
authors: Yu-Cheng
authors: YC
authors: Chang
authors: Hui-Ping
authors: HP
authors: Wu
authors: Nagannagari Masi
authors: NM
authors: Reddy
authors: Hsuan-Wei
authors: HW
authors: Lee
authors: Hsueh-Pei
authors: HP
authors: Lu
authors: Chen-Yu
authors: CY
authors: Yeh
authors: Eric Wei-Guang
authors: EW
authors: Diau
mesh_terms: D011211:Electric Power Supplies; D004583:Electrons; D007700:Kinetics; D011166:Porphyrins / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D012993:Solar Energy
chemical_list: D011166:Porphyrins; D011725:Pyridines; C582866:4-tert-butylpyridine