| Since 2009,the perovskite solar cells have developed in a first decade,the authentication efficiency has increased from the original less than 4 % to current25.2 %.And it shows great potential applications in tandem solar cells,building integrated photovoltaics,wearable electrics,etc.In the structures of perovskite solar cells,the electrode is an essential component,which not only transfers photo-generated charge carriers to the external circuit in photovoltaic conversion process,but also plays an important role in the quality of interface layer,the transparency and cost of photovoltaic devices.According to the requirements of photovoltaic device research in recent years,more and more products are developing towards the direction of light,transparency and integration,which puts forward high requirements for active layers of perovskite solar cells,and provides the electrodes with high performance and low cost.This paper is focused on the optimization and fabrication of perovskite solar cell electrodes,including the following parts:1.By introducing small amount of graphene oxide sheets(GOSs)on indium tin oxide(ITO)bottom electrode act as the nucleation sites in the crystal growth process of perovskite films.The nucleation barrier of perovskite crystal was reduced under the effect of GOSs,and the O in GOSs formed Pb-O bond with Pb in perovskite,both result in dramatically improved morphology and crystallization of the perovskite films.The compact perovskite active layer effectively reduces the charge combination between the electrode and the perovskite interface,omits the expensive hole transport layer,thus significantly reduced the cost of the perovskite solar cell preparation.Finally,the hole-transport layer-free perovskite solar cell based on modified ITO bottom electrode with GOSs achieved 6.62% photoelectric conversion efficiency(PCE),which is about 40% higher than the reference device.2.Silver nanowires(Ag NWs)transparent conductive film can be prepared by solution method at low temperature.Low density Ag NWs network can achieve high transmittance and excellent conductivity.However,the use of insolating polyvinyl pyrrolidone(PVP)surfactant hinders the contact between nanowires and nanowires,thus limits the conductivity of the final Ag NW networks.By introducing a small amount of deionized water into Ag NWs dispersion in isopropanol,morphology analysis confirmed that water is able to wash PVP away from the Ag NWs surface and resulting in a cold welding of nanowires,the spray-coated AgNWs film showed an averaged sheet resistance(Rs)of 27 ?/?with an averaged light transparence(AVT)of 91% significantly improved compared with the reference Ag NWs film(AVT of 90.8% and Rs of 120.9?/?).The optimized Ag NWs was spray coated on the top of perovskite solar cell acted as top electrode.Finally,the all solution-processed semi-transparent perovskite with high PCE of 14.04% and averaged light transmittance of 21.7% are achieved.3.ITO transparent conductive film is commonly used as bottom electrode of perovskite solar cells,but it is expensive and contains rare element indium,make it not conducive to reduce the preparation cost of perovskite solar cells.Here in,the traditional expensive ITO was replaced by the evaporated Al as the base electrode.Under the modification of Mo O3,the energy barrier between Al and the upper interface layer could be successfully leveled.The Al/Mo O3 composite electrode and the optimized Ag NWs transparent electrode were used as the bottom and top electrode of perovskite solar cells,respectively.By optimizing the thickness of Al and Mo O3,a low-cost perovskite solar cell with PCE of 6.23% was successfully obtained. |
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