A Mixed Antisolvent-Assisted Crystallization Strategy for Efficient All-Inorganic CsPbIBr₂ Perovskite Solar Cells by a Low-Temperature Process

Abstract

To improve the microstructure of low-temperature-processed CsPbIBr2 films, a chlorobenzene (CB) and isopropyl alcohol (IPA) mixed solution is used as an antisolvent to fabricate CsPbIBr2 films. It is found that the modified film by the mixed antisolvent demonstrates a better morphology, crystallinity, absorption of sunlight, less trap-state density (N trap), and suppressed carrier recombination. The modified perovskite solar cells (PSCs) without a hole-transport layer (HTL) achieve a champion efficiency of 7.05%, being much higher by 28.18% than that of the Reference-PSCs without an antisolvent. Moreover, the HTL of undoped zinc phthalocyanine (ZnPc) prepared by solution processing is used to promote charge transfer and protect the CsPbIBr2 film from damage caused by humid air at the CsPbIBr2/carbon interface. The best PSC with a structure of FTO/TiO2/CsPbIBr2/ZnPc/carbon yields a champion efficiency of 8.48% (Reference-PSC, 5.50%) with an open-circuit voltage of 1.23 V. The modified PSCs without encapsulation demonstrate improved humidity stability and retain about 90% (Reference-PSC, ∼70%) of their initial efficiency after storage at a 20% relative humidity in air for 30 days. In addition, the modified PSCs possess good light and thermal stability. Our work provides a feasible low-temperature (150 °C) process to prepare CsPbIBr2 films with the preferred orientation and stable, efficient all-inorganic PSCs (200 °C).

Multidimensional Function Upgradation of All‐Inorganic CsPbIBr2 Perovskite Film by Doping an Ionic Additive for Carbon–Electrode‐Based Solar Cells

“…To confirm this conclusion, as shown in Figure 3b, electrochemical impedance spectroscopy (EIS) plots were further conducted to investigate the resistance for charge recombination. Obviously, by fitting the Nyquist plots according to the equivalent circuit, consisting of a series resistance (R s ) and the recombination resistance (R rec ), the enlarged R rec undoubtedly demonstrates the suppressed charge recombination because of the improved film quality and passivated defects, [36] agreeing well with the prolonged electron lifetime…”

“…To confirm this conclusion, as shown in Figure 3b, electrochemical impedance spectroscopy (EIS) plots were further conducted to investigate the resistance for charge recombination. Obviously, by fitting the Nyquist plots according to the equivalent circuit, consisting of a series resistance ( R s ) and the recombination resistance ( R rec ), the enlarged R rec undoubtedly demonstrates the suppressed charge recombination because of the improved film quality and passivated defects, [ 36 ] agreeing well with the prolonged electron lifetime (Figure S7, Supporting Information). Steady photoluminescence (PL) spectra and time‐resolved PL (TRPL) decay curves were further performed to understand the charge recombination behavior in the perovskite films (Figure S8, S9 and Table S1, Supporting Information).…”

Recent Progress of Carbon‐Based Inorganic Perovskite Solar Cells: From Efficiency to Stability

“…However, the low coverage of QDs does not maximize hole extraction ability. The addition of HTLs or defect repair materials at the CsBX 3 /carbon interface can effectively solve this problem, including organic small molecules (e.g., 2‐(3,5‐bis(5‐(5‐hexylthiophen‐2‐yl)thiophen‐2‐yl)thiophen‐2‐yl)‐3,5‐bis(5‐(5‐hexylthiophen‐2‐yl)thiophen‐2‐yl)thiophene (BT‐BTH), [ 332 ] tin phthalocyanine (SnPc), [ 27 ] ZnPc, [ 333 ] Cu‐phthalocyanine (CuPc) [ 334 ] or its derivative, [ 335 ] etc. ), 2D nanomaterials (e.g., graphene oxide (GO), [ 303 ] (NiCo) 1‐ y Fe y O x nanoparticles decorated GO (NP‐GO), [ 336 ] rhenium disulfide (ReSe 2 ), [ 122 ] etc.)…”

Wide-bandgap perovskites for multijunction solar cells: improvement of crystalline quality of Cs0.1FA0.9PbI1.4Br1.6 by using lead thiocyanate

“…Some methods have been reported to solve these issues, such as additive incorporation, anti-solvent treatment, Lewis acid-base adduct, and vaporassisted deposition. [27][28][29][30][31][32][33] Pb(SCN) 2 is a popular additive and has been reportedly used in MA-based solar cells to control crystal nucleation, passivate GBs, and enhance the long-term stability of the device. [34][35][36][37] In this study, to fabricate highquality Cs 0.1 FA 0.9 PbI 1.4 Br 1.6 thin lms, we added Pb(SCN) 2 into perovskite precursor solutions and investigated the inuence of the concentration of Pb(SCN) 2 on the device performance ofCs 0.1 FA 0.9 PbI 1.4 Br 1.6 -based solar cells.…”