Yer to improve the resistance to intrinsic and extrinsic degradation [162]. The reactions is usually described as follows [163]: 2PEAI PbI2 2BAI nPbI2 nMAI(PEA)2 PbI(BA)two MAn-1 Pbn I3n1 MAILi et al. introduced suit development of gradient diffusion 2D pure PEA2 PbI4 in 3D MAPbI3 ; each the 2DD mixed devices and 2DD gradient devices exhibited enhanced moisture stability soon after 15 days of storage in an air atmosphere with 35 55 humidity, which could be as a consequence of hydrophobic benzene groups in PEA , plus the 2DD gradient devices showed great operation stability at maximum power point under AM 1.5G illumination with 100 mW/cm2 more than 1000 h relative towards the typical 3D PSCs [162]. You et al. reported yet another powerful system in defect passivation, and they deposited organic halide salt PEAI, in lieu of 2D PEA2 PbI4 perovskite, on the Goralatide web perovskite (FA1-x MAx PbI3) to suppress the surface defects and to reduce non-radiative recombination, by which wonderful improvement of thermal stability was accomplished. The PCE with the PEAI-treated device decreased at the start off of quite a few hours of annealing at 85 C, and after that the efficiency remained almostMaterials 2021, 14,20 ofconstant as much as 500 h [12]. FAPbI3 is recognized to undergo phase conversion beneath ambient -Timolol supplier conditions, but the propriate 2D adducts can stabilize the cubic structure of FAPbI3 . Lee et al. incorporated 1.67 mol PEAI into the perovskite precursor answer to guard the FA-based perovskite from moisture and suppress ion migration; the ready devices with efficiency above 20 maintained 98 of their initial PCE just after 1392 h in dark [164]. Introducing each Pb(SCN)two and PEAI to perovskite precursor to kind 2D or quasi-2D materials is an efficient method to improve the operational stability of PSCs. Kim et al. regulated the doping concentration of PEAI and Pb(SCN)two and fabricated devices with outstanding stability that could keep more than 80 of the initial PCE of 20.7 after 1000 h of continuous illumination [165], as well as other work based on exactly the same dopants with diverse proportion showed four degradation under storage at area temperature within a N2 environment for longer than 4000 h (Figure 11a). [165] Zheng’s group studied the length of diverse surface-anchoring alkylamine ligands (AAL), and perovskite film with long-alkyl-chain AALs (OA or OAm) exhibited longer carrier lifetimes (Figure 11b) and bigger water contact angles. The AAL-modified perovskite showed additional n-types, and the ion migration was hindered, which have been effective towards the stability. The devices with AALs exhibited no PCE loss just after continuous operation for 1000 h under AM1.5 illumination inside a N2 atmosphere having a UV filter using a 420-nm cut-off, and lost only around ten of their initial PCE soon after a thermal stability test of 1020 h (T = 85 C) (Figure 11c) [166].Figure 11. (a) Long-term stability of perovskite devices with distinct 2D additives beneath light illumination without encapsulation [165]. (b) Arrhenius plots (obtained by linear fitting of data points) with the temperature dependence of T/, showing an ion migration activation power (Ea) for pristine films and films with AALs, respectively [166]. (c) Long-term stability of the pristine CsFAMA device and the CsFAMA device with AALs below continuous simulated solar illumination (100 mW cm-2) inside a N2 atmosphere using a UV filter using a 420-nm cut-off [166].Operates on the substitution of Pb2 to improve stability have produced some progress. Ion dopants (e.g., Zn2 , Mn2) having a smaller sized ionic radius tha.
