Efficiency enhancement in bulk-heterojunction solar cells integrated with large area Ag nano-triangle arrays

• Main Authors: Wu, Bo, Oo, Than Zaw, Li, Xianglin, Liu, Xinfeng, Wu, Xiangyang, Yeow, Edwin Kok Lee, Fan, Hong Jin, Mathews, Nripan, Sum, Tze Chien
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2012
• Subjects: DRNTU::Science::Mathematics
• Online Access: https://hdl.handle.net/10356/95412; http://hdl.handle.net/10220/8283
• Institution: Nanyang Technological University

Efficiency enhancement in plasmonic bulk heterojunction (PCDTBT:PCBM) organic solar cells (OSCs) is demonstrated with the integration of large area periodic Ag nano-triangle (NT) arrays (that were fabricated using the cost-effective, high throughput nanosphere lithography technique) in the OSC device. The improvements to the power conversion efficiency (from 4.24% to 4.52%) and to the short circuit current density (by ~12%) are attributed to an increase in exciton generation induced by the strong local E-field and the scattering generated by the localized surface plasmon resonance of the hexagonal NT arrays. These findings are validated by a range of steady state and transient optical spectroscopy and correlated with device performance data. Importantly, our work demonstrates the feasibility of integrating a simple cost-effective, tailorable and scalable nanofabrication technique with existing OSC fabrication processes.