Enhanced performance of PTB7-Th:PCBM based active layers in ternary organic solar cells

Govinda Lakhotiya; Namdeo Belsare; Sudhir Arbuj; Bharat Kale; Abhimanyu Rana

doi:10.1039/c8ra08919a

Enhanced performance of PTB7-Th:PCBM based active layers in ternary organic solar cells

RSC Adv. 2019 Mar 6;9(13):7457-7463. doi: 10.1039/c8ra08919a. eCollection 2019 Mar 1.

Authors

Govinda Lakhotiya^{1

2}, Namdeo Belsare², Sudhir Arbuj³, Bharat Kale³, Abhimanyu Rana⁴

Affiliations

¹ Department of Physics, Jankidevi Bajaj College of Science Wardha 442001 India lakhotiya.govinda@gmail.com.
² Department of Physics, Vidyabharati Mahavidyalaya Amravati 444602 India.
³ Centre for Materials for Electronics Technology Panchwati, Off Pashan Road Pune 411008 India.
⁴ School of Engineering and Technology, BML Munjal University Gurgaon 122413 India rana.abhimanyu@gmail.com.

Abstract

The present study aims at understanding the role of incorporating Cu₂S nanocrystals (NCs) as a third component in ternary organic solar cells. Ternary photoactive blends consisting of conjugated polymer poly[4,8-bis(5-(2-ethylhexyl)thiophen-2-yl)benzo[1,2-b;4,5-b']dithiophene-2,6-diyl-alt-(4-(2-ethylhexyl)-3-fluorothieno[3,4-b]thiophene-)-(2-carboxylate-2-6-diyl)] (PTB7-Th), fullerene derivative phenyl-C₇₁-butyric acid methyl ester (PCBM) and different wt% of Cu₂S NCs were formulated and were employed to fabricate ternary OSCs having a device architecture of ITO/ZnO/PTB7-Th:Cu₂S NCs:PCBM/MoO₃/Ag. It has been observed that with the addition of 3 wt% of Cu₂S NCs, an improved power conversion efficiency (PCE) of 8.20% is obtained against the PCE of 6.96% for reference devices. EIS measurements and AFM studies suggests that the presence of Cu₂S NCs facilitates formation of cascading energy levels, provides smoother surfaces and helps in suppressing trap-assisted recombination.