Negative capacitance and hysteresis in encapsulated MAPbI3 and lead–tin (Pb–Sn) perovskite solar cells

Crystal structure and optical characterization of a new hybrid compound, C6H9N2FeCl4, with large dielectric constants for field-effect transistors

“…These states can result in the creation of an interfacial space charge at the interface. 95,96 The contribution of the ionic capacitance decreased with the drop in temperature. However, at high frequencies, the capacitance became saturated and plateaued.…”

Selection of hole transport layer for Pb-Sn binary perovskite solar cells

“…Among these three HTLs, CuI has higher and PTAA has lower hysteresis loss. However, hysteresis not only depends on the HTLs, it also depends on other several factors such as device structures, the interface, ion migration, charge capture, carrier accumulation at the interface, scanning rate, scanning range, pre-treatment and ambient temperature [21]- [23]. Charge separation at the HTL/perovskite interface plays a significant role in the hysteresis.…”

“…Charge separation at the HTL/perovskite interface plays a significant role in the hysteresis. Comparing among three PTAA/perovskite has smaller local electric field and as a result faster positive carrier separation is happening and getting lower hysteresis [21]. The photovoltaic performance parameters of these three kinds of solar cells are tabulated in table 2.…”

Beyond Protocols: Understanding the Electrical Behavior of Perovskite Solar Cells by Impedance Spectroscopy

“…The assessment of hysteresis with IS has been discussed in recent studies. [19,42,43] Gonzales et al, formulated a general model to correlate IS data and device hysteresis at different voltages of the J-V curve in PSCs. [42] The model was used to evaluate hysteresis via the impedance parameters and track transitions between capacitive and inductive domains at low and high voltages, respectively.…”

“…Most of the impedance spectra of PSCs comprise two or three arcs in the impedance Nyquist plot and two or three plateaus in the C-f plot which represent the real part of the capacitance versus frequency in logarithmic scale. [18] More complicated spectra include features such as further resistance-capacitance R-C arcs/plateaus, negative capacitances, [19,20] and/or inductive loops can be observed in the Nyquist plots. [21,22] Negative capacitance refers to the low frequency arc below the real Z-axis (Z′) and inductive loop appears as two arcs crossing each other at the intermediate/low frequencies (see Section 1.3).…”