Perovskite CH₃NH₃PbI_3–XCl_x Solar Cells. Experimental Study of Initial Degradation Kinetics and Fill Factor Spectral Dependence

Abstract

The main drawback of the methylammonium lead halide perovskite solar cells is their degradation in ambient atmosphere. To investigate ambient-air-induced cell degradation, spectral dependencies of open-circuit voltage (VOC), fill factor (FF) and the power conversion efficiency (PCE) have been acquired (for the first time reported in literature).Our custom-made measurement system allowed us to perform measurements of the abovementioned entities in situ directly in vacuum during and after thermal deposition of the electrode. We also studied how these parameters in vacuum changed after cell exposure to ambient air for 85 min (50 nm top electrode) and for 180 min (100 nm top Ag electrode). For fresh CH3NH3PbI3–xClx cell (never been in open air) with very high shunt resistance of 3·107 Ω·cm2 (with practically no shorts and therefore FF could be determined mainly by charge carrier recombination processes) we found that FF in vacuum increased along with an increase of the incident photon energy from 0.55 at 760 nm up to 0.82 at 400 nm. Hypothesis considering hot polaron participation in charge carrier photogeneration and recombination processes as well as another competing hypothesis were offered as possible explanations for the observed FF increase.The kinetics of short-circuit photocurrent EQE with a change in pressure was also investigated. It was also shown that perovskite solar cell degradation could be noticeably reduced by increasing the top Ag electrode thickness to at least 100 nm, which could possibly facilitate the usual encapsulation process.

Features of model thin-film solar cells photoelectric characteristics based on a non-toxic multi-component connection CuZn2AlS4

“…Recently, active work is underway to introduce alternative sources of electricity in various industries based on photovoltaic modules that use solar energy [2]. Despite the wide production of silicon-based solar cells, other materials are intensively used to improve the output energy characteristics of photovoltaic modules (see, for example, [3][4][5]). The search and synthesis of new materials with unusual properties, used to create new types of solar cells, and the modernization of the properties of existing types of solar cells by improving the technology of their manufacture and processing will mainly determine the progress in solar energy.…”

Influence of “Productive” Impurities (Cd, Na, O) on the Properties of the Cu2ZnSnS4 Absorber of Model Solar Cells

“…Note that various options have already been proposed and successfully developed for energy converters, such as solar batteries [1]- [3], wind generators [4], [5], geothermal converters [6], as well as for different energy storage devices, such as a superconducting inductive storage [7]. To improve the performance of these systems, new properties of solar radiation absorbers [8]- [10], quasi-two-dimensional materials [11]- [13], superconductors [14]- [16] and others are being searched.…”