نقش نقاط كوانتومي گرافن در بهبود عملكرد سلول هاي خورشيدي پروسكايتي متخلخل

چكيده انگليسي :

98AbstractGiven the increasing energy demand and depleting fossil fuels development of solar cells hasgained considerable importance in recent years Among different generations of solar cells perovskite solar cells have received considerable attention due to their easy fabrication process andrelatively rapid increase of their power conversion efficiency PCE In this regard the use ofcarbon derivatives in PSCs structure has been introduced as an effective approach to improve thecell performance The aim of the present study was to investigate the role of graphene quantumdots GQDs that were synthesized from fenugreek leaves in improving the performance ofmesoscopic PSCs For this purpose first effects of adding graphene quantum dots GQDs to themesoscopic TiO2 mp TiO2 ETL on the photovoltaic performance and stability of PSCs wereinvestigated Then the effects of GQDs doped perovskite layer as the light absorbing layer ofPSCs on the PSCs performance were also evaluated Before examining the effects of GQDsaddition to the PSCs structure and in order to choose the efficient perovskite material theperformance of Cs0 05 MA0 17FA0 83 99 95Pb I0 83Br0 17 3 cation anion mixed perovskite based PSCswas compared with that of the PSCs based on CH3NH3PbI3 as a usual perovskite material Moreover considering the importance of the mesoscopic TiO 2 layer in PSCs the effects of theratio of TiO2 paste to ethanol as pure TiO2 layer precursor materials on the cell performance werealso investigated to achieve the most optimal TiO2 performance The results confirmed that thedoping of TiO2 and perovskite layers with GQDs have been successful The findings revealed thatGQDs addition to mesoscopic TiO2 layer could improve the quality of perovskite film in terms ofdefect states and structure density improve the TiO2 perovskite interface quality facilitatephotogenerated carriers transport and suppress recombination processes Compared to pure TiO2ETL based PSC the Jsc from 15 16 mA cm 2 to 21 92 mA cm 2 Voc ftom 0 88 V t0 0 97 FF from 0 60 to 0 67 and PCE from 9 55 to 14 36 of PSC based on 2 5 vol GQDs dopedTiO2 ETL as a champion cell were significently boosted Moreover the PSC based on 2 5vol GQDs TiO2 ETL maintained 88 of its initial PCE after 500 h whereas the conventionalPSC based on pure TiO2 ETL maintained only 58 of its initial PCE under the same conditions Interestingly GQDs addition to the perovskite layer resulted in the improvement of perovskitelayer quality and the facilitation of electron transfer ultimately improving the PV performance andstability of the fabricated PSCs The 7 vol GQDs perovskite layer based PSC as a superior cell exhibited Jsc Voc and FF of 20 63 mA cm 2 0 99 V and 0 66 respectively corresponding to a PCEof 13 67 This PCE was approximately 30 higher than that of pure perovskite layer based PSC Furthermore the 7 vol GQDs perovskite layer based PSC was able to maintain about 90 of itsinitial PCE after 500 h whereas the PSC based on pure perovskite layer was able to maintain only58 of its initial PCE under the same conditions The results of the present study indicated that theuse of GQDs in the PSCs structure can be an effective and simple approach to simultaneouslyimprove the efficiency and stability of the mesoscopic PSCs Keywords Perovskite solar cells Graphene quantum dots Electron transport layer Light absorbing perovskite layer Power conversion efficiency Stability

ابراهيمي، مرضيه

نقش نقاط كوانتومي گرافن در بهبود عملكرد سلول هاي خورشيدي پروسكايتي متخلخل

سلول خورشيدي پروسكايتي. , نقاط كوانتومي گرافن , لايه انتقال دهنده الكترون , لايه جاذب نور پروسكايت , بازده تبديل توان , پايداري