Bridging For Carriers In The Photoactive Layer To Enhance Performance Of Polymer Solar Cells

Polymer solar cells?PSCs?have attracted extensive attention in the past few decades by virtue of their superior features including light weight,mechanical flexibility,solution processing,low cost and easy roll-to-roll production in a large scale etc.Although significant breakthrough in device performance of PSCs has been achieved continuously,and the power conversion efficiency?PCE?of PSCs has exceeded 17%,there is still much room for improvement compared with inorganic solar cells.It is well known that the contradiction between effective carrier collection and efficient light absorption for PSCs is one of the main factor,which limit the performance improvement of PSCs.As a consequence,numerous investigations were carried out to relieve the contradiction,including the bulk heterojunction configuration,surface plasmon resonance technology and light management structures etc.This article mainly studies the effect of oxide nanoparticles on the performance of P3HT:PC₆₁BM PSCs,explores and summarizes research schemes to improve the performance of P3HT:PC₆₁BM PSCs.The research work of this paper mainly includes the following aspects:?1?In order to improve the charge collection efficiency at the electrodes of PSCs,the anhydrous ethanol solution of zirconium acetylacetonate was spin-coated between the active layer and the negative electrode as electron transfer layer.The experimental results show that the electron transfer layer of zirconium acetylacetonate can improve the performance of the device.As a result,the optimal PCE is 2.41%,which is increased 19.31%?reference device 2.02%?.?2?The SnO₂ nanoparticles were embeded into the active layer to build“electron bridge”to increase the exciton dissociation rate and electron transport,which decrease the recombination in the active layer and improve the FF of device.At the same time,the photocurrent of the device was increased by light scattering of SnO₂ nanoparticles.Finally,the PCE has increased 26.97%compared with the reference device.?3?ZnO and NiO_x nanoparticles were embeded into the active layer simultaneously to build“electron bridge”and“hole bridge”to increase the exciton dissociation rate and carriers transport,which decrease the recombination of electron and hole.The experimental results show that the introduction of two kinds of nanoparticles significantly improves the exciton dissociation.And the photocurrent of the device was increased by light scattering of ZnO nanoparticles.In summarize,the PCE of the device reach 3.12%increased 57.58%.