Enhancing Stability and Photostability of CsPbI₃ by Reducing Its Dimensionality

Abstract

Full inorganic perovskites display their poten tial to function as stable photovoltaic materials better than the hybrid organic-inorganic perovskites. However, to date, the cesium lead iodide perovskite, which displays a promising absorbance range, has suffered from low stability, which degrades to a nonactive photovoltaic phase rapidly. ln this work, we show that the black phase of cesium lead iodide can be stabilized when the perovskite dimensionality is reduced. X ray diffraction, absorbance, and scanning electron micros copy were used to follow the degradation process of various dimensionalities under room conditions and 1 sun illumina tion. When comparing the effect on the stability and Time) •••••••• photostability of cesium lead iodide with linear or aromatic barrier molecules, the aromatic barrier molecule displays better photostability for over 700 h without degradation under continuous 1 sun illumination than does the linear barrier molecule. Theoretical calculations show that the addition of the barrier molecule makes a different charge distribution over the perovskite structure, which stabilizes the CsPbl 3 black phase. This work provides the possibility to use the CsPbl 3 perovskite as a stable photovoltaic material in solar cells.

Ruddlesden–Popper 2D Component to Stabilize γ‐CsPbI3 Perovskite Phase for Stable and Efficient Photovoltaics

“…1) 0D quantum dots (QDs): Reducing the crystal size will led to more surface to accommodate organic group, which makes the α-CsPbI 3 more stable. [51] However, the PCE of these devices are below 7%. [48] Xi et al employed with H 2 PbI 4 and assistant doping with Mn 2+ to stabilize the unstable core lattices.…”

“…[50] Etgar and co-workers also showed when the α-CsPbI 3 dimensionality is reduced, the black phase of α-CsPbI 3 could be stabilized. [51] However, the PCE of these devices are below 7%. 3) Quasi-2D structure: Yuan and co-workers introduced a judicious amount of PEAI and fabricated quasi-2D α-CsPbI 3 .…”

Spatial Distribution Recast for Organic Bulk Heterojunctions for High‐Performance All‐Inorganic Perovskite/Organic Integrated Solar Cells

“…[1][2][3] Tremendous differences in the moisture/light stability and efficiency of all-inorganic perovskites are greatly affected by the halogen I content (or the I/Br ratios). [4][5][6][7][8] Inorganic perovskite with a CsPbIBr 2 formula is considered to be the best option because of its balanced bandgap and stability for potential application in solar cells. [9] In addition, CsP-bIBr 2 perovskite possesses an imperative bandgap of 2.1 eV with a high absorption coefficient in ultraviolet (UV) light region showing a bright-red color, which makes CsPbIBr 2 a promising wide-bandgap component for applications in integrate/tandem solar cells with a UV-filter All-inorganic CsPbIBr 2 perovskite solar cells (pero-SCs) exhibit excellent overall stability, but their power conversion efficiencies (PCEs) are greatly limited by their wide bandgaps.…”

The properties, photovoltaic performance and stability of visible to near-IR all inorganic perovskites

“…27 The transition between the phases usually happens due to exposure to air when the a phase, which is cubic, transforms to the b phase (tetragonal structure) and then to the g and d phases (orthorhombic structure). In our previous report, we showed that CsPbI 3 can be stabilized in a two dimensional structure (2D); 28 however, it forms a wide band gap, which makes it problematic to function efficiently in a solar cell. 29 Other methods to stabilize the CsPbI 3 active phase include the addition of different salts such as EuBr 2 , EuCl 2 , and CaI 2 .…”

“…29 Other methods to stabilize the CsPbI 3 active phase include the addition of different salts such as EuBr 2 , EuCl 2 , and CaI 2 . [25][26][27][28][29][30][31] Modifying the B site in CsPbI 3 can tune the optical properties and at the same time can enhance its stability. The replacement of lead (Pb) by tin (Sn) in the case of MA + based perovskites leads to a variation in the band gap from 1.55 eV for MAPbI 3 to 1.3 eV for MASnI 3 .…”