Effect of Rubidium Incorporation on the Structural, Electrical, and Photovoltaic Properties of Methylammonium Lead Iodide-Based Perovskite Solar Cells

Abstract

We report the electrical properties of rubidium-incorporated methylammonium lead iodide ((RbMA)PbI) films and the photovoltaic performance of (RbMA)PbI film-based p-i-n-type perovskite solar cells (PSCs). The incorporation of a small amount of Rb (x = 0.05) increases both the open circuit voltage (V) and the short circuit photocurrent density (J) of the PSCs, leading to an improved power conversion efficiency (PCE). However, a high fraction of Rb incorporation (x = 0.1 and 0.2) decreases the J and thus the PCE, which is attributed to the phase segregation of the single tetragonal perovskite phase to a MA-rich tetragonal perovskite phase and a RbPbI orthorhombic phase at high Rb fractions. Conductive atomic force microscopic and admittance spectroscopic analyses reveal that the single-phase (RbMA)PbI film has a high electrical conductivity because of a reduced deep-level trap density. We also found that Rb substitution enhances the diode characteristics of the PSC, as evidenced by the reduced reverse saturation current (J). The optimized (RbMA)PbI PSCs exhibited a PCE of 18.8% with negligible hysteresis in the photocurrent-voltage curve. The results from this work enhance the understanding of the effect of Rb incorporation into organic-inorganic hybrid halide perovskites and enable the exploration of Rb-incorporated mixed perovskites for various applications, such as solar cells, photodetectors, and light-emitting diodes.

Effects of Iodine Doping on Carrier Behavior at the Interface of Perovskite Crystals: Efficiency and Stability

“…It can be seen that the V oc was immediately increased from 0.92 V (average) to over 1 V due to spiro-OMeTAD + formation. According to the definition, the V oc is related to both light-generated current and saturation current [28], as shown by Equation (1):…”

Secondary Ion Mass Spectrometry (SIMS) for Chemical Characterization of Metal Halide Perovskites

“…Park et al unveiled that incorporating excessive Rb + in MAPbI 3 will lead to significant Rb + segregation. [45] Hu et al also found that the Rb + accumulates at the TiO 2 /perovskite interface in the 5% Rb doped FA 0.83 MA 0.17 Pb(I 0.83 Br 0.17 ) 3 perovskite. [46] On the contrary, the Cs + is evenly distributed within the 5% Cs doped FA 0.83 MA 0.17 Pb(I 0.83 Br 0.17 ) 3 perovskite films.…”

Impedance Spectroscopy of Perovskite Solar Cells: Studying the Dynamics of Charge Carriers Before and After Continuous Operation

“…The built-in potential and defect density could be obtained from the voltage intercepts and from the slope, respectively, by fitting the C À2 with respect to the bias in the C s region. In the Mott-Schottky plot, C À2 and V are related by [38][39][40][41] 1…”