Professor Ziyi Ge's research team at the Chinese Academy of Sciences’ (CAS) Ningbo Institute of Materials Technology and Engineering (NIMTE) has created high-performance flexible organic solar cells (OSCs) with good thermal stability and stretchability, accomplishing power conversion efficiency effectiveness (PCE) of over 16.5%.
Schematic illustration of the fracture mechanisms of ternary blend films and J–V curves of the flexible device. Image Credit: Ningbo Institute of Materials Technology and Engineering.
The observations were published in the journal Matter.
The researchers at NIMTE added polymer guests to the PM6:BTP-eC9 blend film to construct entangled chain networks, which enhanced the blend film’s ductility and morphological stability.
The crack-onset strain of the developed ternary blend membrane is 17.14% greater than that of the traditional binary blend membrane due to the efficient dissipation of local load induced by the entangled structure.
Furthermore, thanks to the ternary heterojunction strategy, a stabilized PCE of 16.52% was obtained for polyethylene terephthalate-substrate-based flexible OSCs with outstanding bending tolerance.
The PCE of the inverted ternary OSCs maintained over 85.5% (about 7.2% greater than the binary system) of its initial efficiency after 250 hours when stored in an N2-filled glove box at 85 °C, denoting remarkable thermal stability.
Furthermore, the ternary OSCs demonstrated excellent stretchability, with PCE retention of over 88% (roughly 13% higher than the binary system) after 200 stretching cycles at a tensile strain of about 5%.
The study was supported by the National Science Fund for Distinguished Young Scholars, the National Natural Science Foundation of China, the Ningbo S&T Innovation 2025 Major Special Programme, the Key Project of Frontier Science Research of CAS, etc.
Journal Reference:
Song, W., et al. (2022) Entangled structure morphology by polymer guest enabling mechanically robust organic solar cells with efficiencies of over 16.5%. Matter. doi.org/10.1016/j.matt.2022.03.012.
Source: https://english.cas.cn/