Development of semitransparent Perovskite Solar Cells with double electron transport layer and modified top electrode
In this work we report on semitransparent perovskite solar cell fabrication using double electron transport layer and double top electrode. Such devices may be used in tandem solar cells which are made to overcome Shockley-Queisser limit for one junction solar cell and improve efficiency of the device. One of the main issues of this task is to make transparent top electrode since it is usually made of metal. In this work the combination of ITO/Ag is used in which silver is deposited via special mask to improve conductivity. Top ITO electrode was deposited via magnetron sputtering – the process was optimized for room temperatures to avoid perovskite and organic degradation. ZnO nanoparticles are incorporated in device as second electron transport layer to protect all below layers from ITO sputtering damage. This layer was deposited via spin-coating process, which is much easier and faster than atomic layer deposition, which is usually used for ZnO deposition. The best semitransparent perovskite solar cell made with these modifications showed 11.5% efficiency with high VOC value of 1.1 V.