Harnessing plasmon-exciton energy exchange for flexible organic solar cells with efficiency of 19.5%

The plasmonic effects have unlocked remarkable advancements in modern optoelectronics, enabling enhanced light-matter interactions for applications ranging from sensing to photovoltaics. However, the nonradiative damping of plasmonic effects causes parasitic absorption which limits the light-utilization efficiency of optoelectronics, particularly for photovoltaic cells. Herein, we propose a plasmon energy recycling scheme consisting of green fluorophore (BCzBN) and nickel oxide to compensate for the plasmon energy loss. The plasmons trapped in silver nanowire (AgNW) electrodes are coupled to green emission through plasmon-exciton energy exchange. Backward electron and energy transfer are inhibited due to the spectral mismatch and energy level offset. The optically enhanced flexible AgNW electrode exhibits an improvement of 10.74% in transmittance, yielding flexible organic solar cells with an efficiency of 19.51% and a certified value of 18.69%. This innovative strategy provides a pathway for overcoming plasmon energy losses in plasmonic optoelectronics, opening horizons for highly efficient flexible photovoltaics and plasmonic devices.