Optoelectronic and morphology properties of perovskite/silicon interface layer for tandem solar cell application

Abstract

Silicon (Si) solar cell has low optical absorption because of the low and indirect bandgap of Si, and the efficiency was trapped at 25% for 15 years. Si solar cell is able to achieve efficiency up to 30% by adding perovskite as multiple bandgap material through tandem formation. In this paper, the Si/perovskite interface layer was characterized to study the compatibility of perovskite on fluorine‐doped tin oxide (FTO) glass and p‐type Si wafer (p‐Si). The single solution deposition step of methyl ammonium lead iodide, CH3NH3PbI3(MAPbI3) perovskite film, was spin‐coated at different concentration. The physical properties of the MAPbI3/FTO and MAPbI3/p‐Si were obtained by profilometer, atomic force microscope, X‐ray diffraction, and Raman spectroscopy. The optical properties were analyzed by ultraviolet‐visible spectroscopy, photoluminescence, and infrared transmission. Then the electrical properties were measured by Hall effect. From the measurement, it is observed that 1.2M concentration of MAPbI3thin film has the highest thickness, smoothest film surface, and largest crystallite size compared with 0.8M and 1.0M. It is found that there is an interaction in perovskite/Si interface and caused in a low‐wavelength shift, and the increase in concentration of MAPbI3helped in intensifying the Raman signal produced. 1.2M MAPbI3thin film had the highest enhancement in light trapping property rather than 0.8M and 1.0M. The bulk concentration and conductivity of 1.2M perovskite were higher, but the resistivity was lower than 0.8M MAPbI3because of more CH3NH3I and PbI2concentration within MAPbI3perovskite compound.