Molecular insights of non-fused nonfullerene acceptor comprising a different central core for high efficiency organic solar cell

In this study, we applied a strategy which is systematically varying the central' core in non-fused NFA structure to modulate the optical-electrochemical properties and photovoltaic performance. The optical and structural calculation was analyzed via UV–Vis spectroscopy and DFT calculation. The results exhibit that strong NIR absorption and good planar backbone structure on those non-fused NFAs. Consequently, photovoltaic device based on TT linked acceptor delivered a promising photovoltaic efficiency of 8.37% for as-cast device. These results suggest that the change of central unit is an effective strategy to improve the optoelectronic properties of non-fused NFAs in organic solar cells.