Interfacial Kinetics of Efficient Perovskite Solar Cells

Abstract

Perovskite solar cells (PSCs) have immense potential for high power conversion efficiency with an ease of fabrication procedure. The fundamental understanding of interfacial kinetics in PSCs is crucial for further improving of their photovoltaic performance. Herein we use the current-voltage (J-V) characteristics and impedance spectroscopy (IS) measurements to probe the interfacial kinetics on efficient MAPbI 3 solar cells. We show that series resistance (R S ) of PSCs exhibits an ohmic and non-ohmic behavior that causes a significant voltage drop across it. The Nyquist spectra as a function of applied bias reveal the characteristic features of ion motion and accumulation that is mainly associated with the MA cations in MAPbI 3 . With these findings, we provide an efficient way to understand the working mechanism of perovskite solar cells.

Facile NiOx Sol-Gel Synthesis Depending on Chain Length of Various Solvents without Catalyst for Efficient Hole Charge Transfer in Perovskite Solar Cells

“…The series resistances ( R s , charge transport resistance) were 7.45 × 10 1 Ω ( R s1 ) and 2.43 × 10 1 Ω ( R s2 ), which were lower in the “NiO x via B-OH” devices than those in the “NiO x via ET-OH” devices. Therefore, this is consistent with the device performance results, which show an improved J sc and PCE (%), as shown in Table 1 [89,90,91].…”

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 −2 with respect to the bias in the C s region. In the Mott–Schottky plot, C −2 and V are related by [ 38–41 ] where N is the defect density in the perovskite film, q is the elementary charge, ε is the dielectric constant of the perovskite (≈32.5), A is the device area (0.15 cm 2 for both the sample and control cells), V bi is the built in voltage, and ε o is vacuum permittivity. The trap density in the device is extracted from the slope of a Mott–Schottky plot () in the depletion region ( V < V bi ).…”

“…The Mott–Schottky plots comprise two distinct regions which are related to the geometrical capacitance ( C g ) and accumulation capacitance ( C s ), as shown in Figure 5b. [ 38,39 ] The Mott–Schottky plot of the studied solar cells do not show a distinguishable depletion layer capacitance ( C dl ) region. This could be related to the fact that layers containing less defects (films with good crystalline quality) cannot yield distinguishable C dl region in the Mott–Schottky plot representation.…”

“…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…”

Enhancing Optically Pumped Organic-Inorganic Hybrid Perovskite Amplified Spontaneous Emission via Compound Surface Plasmon Resonance

“…Organic-inorganic hybrid perovskites have recently attracted intensive attention for solution-processed optoelectronic devices such as photovoltaics, light-emitting diodes, lasing, and photodetectors, because of their easily tunable optical bandgap, as well as their attractive absorption, emission, and charge transport properties [1][2][3][4][5][6]. Among these applications, the use of perovskites as gain medium in lasing devices has attracted a lot of attention by an increasing number of scientists [7][8][9].…”