Light stability tests of CH₃NH₃PbI₃ perovskite solar cells using porous carbon counter electrodes

Abstract

The CHNHPbI perovskite solar cells have been fabricated using three-porous-layered electrodes as, 〈glass/F-doped tin oxide (FTO)/dense TiO/porous TiO-perovskite/porous ZrO-perovskite/porous carbon-perovskite〉 for light stability tests. Without encapsulation in air, the CHNHPbI perovskite solar cells maintained 80% of photoenergy conversion efficiency from the initial value up to 100 h under light irradiation (AM 1.5, 100 mW cm). Considering the color variation of the CHNHPbI perovskite layer, the significant improvement of light stability is due to the moisture-blocking effect of the porous carbon back electrodes. The strong interaction between carbon and CHNHPbI perovskite was proposed by the measurements of X-ray photoelectron spectroscopy and X-ray diffraction of the porous carbon-perovskite layers.

Research Update: Overview of progress about efficiency and stability on perovskite solar cells

“…Moreover, the perovskite has a strong contact with the porous carbon electrodes, which was confirmed by XRD and XPS. 43 Although the carbon electrodes were a porous layer, the composite of porous carbon and perovskite can block the penetration of moisture to the photovoltaic active parts of solar cells. (3) The group with Han utilized HOOC(CH 2 ) 4 NH 2 (5-aminovaleric acid: 5AVA) in order to improve the contact strength between the CH 3 NH 3 PbI 3 and TiO 2 surface, 41 which prohibit the cleavage of the interface, resulting in the elimination of moisture introduction into the cells.…”

Homogeneous and highly controlled deposition of low viscosity inks and application on fully printable perovskite solar cells

“…The degradation is severe under 1 equivalent sun, as expected for MAPI C-PSCs [35], and hinders any speculations. However, at 0.5 equivalent sun, the devices are stable for over 160 h.…”

Thermal Degradation Analysis of Sealed Perovskite Solar Cell with Porous Carbon Electrode at 100 °C for 7000 h

“…The cells were sealed under ambient conditions with a relatively high humidity of 70 %, so that residual humidity may be present in the porous carbon layer. It should be noted that PCE of perovskite solar cells can be stabilized with the utilization of porous carbon layer, which can work as a good sealing material itself . Magna et al .…”

“…It should be noted that PCE of perovskite solar cells can be stabilized with the utilization of porous carbon layer, which can work as a good sealing material itself. [27] Magna et al reported the degradation of CH 3 NH 3 PbI 3 perovskite crystal under ambient humidity and the reversibility and recovery of the cubic to tetragonal phase transition under inert Ar and N 2 atmospheres. [30] In this work, the recovery of photovoltaic parameters after thermal stress ( Figure 2) is suggested the sufficient barrier using appropriate sealing (Figure 1a) against possible attack by moistures and induced species diffusion.…”