title: Novel metal-free organic dyes possessing fused heterocyclic structural motifs for efficient molecular photovoltaics.
abstract: Reported herein are six novel metal free organic dyes such as PCA1-PCA3 and PCTA1-PCTA3 featuring fused heterocyclic structural motifs such as phenothiazine and alkylcarbazole. Photophysical/electrochemical properties and nanocrystalline TiO2based dye-sensitized solar cell performance of the same have been investigated. Electronic distribution within the molecules has been determined through a computational approach. The overall power conversion efficiencies of the devices with the utilization of dyes PCA1-PCA3 and PCTA1-PCTA3 as sensitizers ranges between 4.67 and 8.08%. The novel dyes possessing cyanoacrylic acid as electron acceptor, PCA1-PCA3, exhibit higher power conversion efficiency, short-circuit current, open-circuit voltage, and electron lifetime those with thioxothiazolidinylacetic acid, PCTA1-PCTA3, as the same. Of the devices fabricated by employing the new metal-free organic sensitizers, that with the dye PCA2 exerted a power conversion efficiency (PCE, η) of 8.08% with a short circuit current density (JSC) of 16.45 mA cm-2, an open circuit voltage (VOC) of 735 mV and a fill factor (ff) of 0.68; this PCE is the highest amongst the devices fabricated.
authors: Department of Chemistry, Kalasalingam University, Krishnankoil - 626 126, Tamilnadu, India. ramalinganc@gmail.com.
authors: Ayyanar
authors: A
authors: Karuppasamy
authors: Department of Chemistry, Kalasalingam University, Krishnankoil - 626 126, Tamilnadu, India. ramalinganc@gmail.com.
authors: Kesavan
authors: K
authors: Stalindurai
authors: Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan. kcho@ntu.edu.tw.
authors: Jia-De
authors: JD
authors: Peng
authors: Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan. kcho@ntu.edu.tw.
authors: Kuo-Chuan
authors: KC
authors: Ho
authors: Department of Chemistry, Kalasalingam University, Krishnankoil - 626 126, Tamilnadu, India. ramalinganc@gmail.com.
authors: Chennan
authors: C
authors: Ramalingan