Self‐Crystallized Multifunctional 2D Perovskite for Efficient and Stable Perovskite Solar Cells

Recently, perovskite solar cells (PSC) with high power‐conversion efficiency (PCE) and long‐term stability have been achieved by employing 2D perovskite layers on 3D perovskite light absorbers. However, in‐depth studies on the material and the interface between the two perovskite layers are still required to understand the role of the 2D perovskite in PSCs. Self‐crystallization of 2D perovskite is successfully induced by deposition of benzyl ammonium iodide (BnAI) on top of a 3D perovskite light absorber. The self‐crystallized 2D perovskite can perform a multifunctional role in facilitating hole transfer, owing to its random crystalline orientation and passivating traps in the 3D perovskite. The use of the multifunctional 2D perovskite (M2P) leads to improvement in PCE and long‐term stability of PSCs both with and without organic hole transporting material (HTM), 2,2′,7,7′‐tetrakis‐(N,N‐di‐p‐methoxyphenyl‐amine)‐9,9′‐spirobifluorene (spiro‐OMeTAD) compared to the devices without the M2P.     

An Ultrathin Ferroelectric Perovskite Oxide Layer for High‐Performance Hole Transport Material Free Carbon Based Halide Perovskite Solar Cells

The hole transport material (HTM) free carbon based perovskite solar cells (C‐PSCs) are promising for its manufactural simplicity, but they currently suffer from low power conversion efficiencies (PCE) largely because of the voltage loss. Here, a new strategy to increase the PCE by incorporating an ultrathin ferroelectric oxide PbTiO₃ layer between the electron transport material and the halide perovskite is reported. The resulting C‐PSCs have achieved PCEs up to 16.37%, which is the highest record for HTM‐free C‐PSCs to date, mainly ascribable to the ferroelectric layer enhanced open circuit voltage. Detail measurements and analysis show an enhanced built‐in potential in the C‐PSCs as well as suppression of the non‐radiative recombination due to the ferroelectric PbTiO₃ layer incorporation, accounting for the boosted V_OC and photovoltaic performance.     

Dithieno[3,2‐b:2′,3′‐d]pyrrol‐Cored Hole Transport Material Enabling Over 21% Efficiency Dopant‐Free Perovskite Solar Cells

Dopant‐free hole transport materials (HTMs) are essential for commercialization of perovskite solar cells (PSCs). However, power conversion efficiencies (PCEs) of the state‐of‐the‐art PSCs with small molecule dopant‐free HTMs are below 20%. Herein, a simple dithieno[3,2‐b:2′,3′‐d]pyrrol‐cored small molecule, DTP‐C6Th, is reported as a promising dopant‐free HTM. Compared with commonly used spiro‐OMeTAD, DTP‐C6Th exhibits a similar energy level, a better hole mobility of 4.18 × 10^?4 cm² V^?1 s^?1, and more efficient hole extraction, enabling efficient and stable PSCs with a dopant‐free HTM. With the addition of an ultrathin poly(methyl methacrylate) passivation layer and properly tuning the composition of the perovskite absorber layer, a champion PCE of 21.04% is achieved, which is the highest value for small molecule dopant‐free HTM based PSCs to date. Additionally, PSCs using the DTP‐C6Th HTM exhibit significantly improved long‐term stability compared with the conventional cells with the metal additive doped spiro‐OMeTAD HTM. Therefore, this work provides a new candidate and effective device engineering strategy for achieving high PCEs with dopant‐free HTMs.     

Synergistic Coassembly of Highly Wettable and Uniform Hole‐Extraction Monolayers for Scaling‐up Perovskite Solar Cells

All organic charge‐transporting layer (CTL)‐featured perovskite solar cells (PSCs) exhibit distinct advantages, but their scaling‐up remains a great challenge because the organic CTLs underneath the perovskite are too thin to achieve large‐area homogeneous layers by spin‐coating, and their hydrophobic nature further hinders the solution‐based fabrication of perovskite layer. Here, an unprecedented anchoring‐based coassembly (ACA) strategy is reported that involves a synergistic coadsorption of a hydrophilic ammonium salt CA‐Br with hole‐transporting triphenylamine derivatives to acquire scalable and wettable organic hole‐extraction monolayers for p–i–n structured PSCs. The ACA route not only enables ultrathin organic CTLs with high uniformity but also eliminates the nonwetting problem to facilitate large‐area perovskite films with 100% coverage. Moreover, incorporation of CA‐Br in the ACA strategy can distinctly guarantee a high quality of electronic connection via the cations' vacancy passivation. Consequently, a high power‐conversion‐efficiency (PCE) of 17.49% is achieved for p–i–n structured PSCs (1.02 cm²), and a module with an aperture area of 36 cm² shows PCE of 12.67%, one of the best scaling‐up results among all‐organic CTL‐based PSCs. This work demonstrates that the ACA strategy can be a promising route to large‐area uniform interfacial layers as well as scaling‐up of perovskite solar cells.     

2D/3D Heterostructure for Semitransparent Perovskite Solar Cells with Engineered Bandgap Enables Efficiencies Exceeding 25% in Four‐Terminal Tandems with Silicon and CIGS

Wide‐bandgap perovskite solar cells (PSCs) with optimal bandgap (E_g) and high power conversion efficiency (PCE) are key to high‐performance perovskite‐based tandem photovoltaics. A 2D/3D perovskite heterostructure passivation is employed for double‐cation wide‐bandgap PSCs with engineered bandgap (1.65 eV ≤ E_g ≤ 1.85 eV), which results in improved stabilized PCEs and a strong enhancement in open‐circuit voltages of around 45 mV compared to reference devices for all investigated bandgaps. Making use of this strategy, semitransparent PSCs with engineered bandgap are developed, which show stabilized PCEs of up to 25.7% and 25.0% in four‐terminal perovskite/c‐Si and perovskite/CIGS tandem solar cells, respectively. Moreover, comparable tandem PCEs are observed for a broad range of perovskite bandgaps. For the first time, the robustness of the four‐terminal tandem configuration with respect to variations in the perovskite bandgap for two state‐of‐the‐art bottom solar cells is experimentally validated.     

Pyrite‐Based Bi‐Functional Layer for Long‐Term Stability and High‐Performance of Organo‐Lead Halide Perovskite Solar Cells

Organo‐lead halide perovskite solar cells (PSCs) have received great attention because of their optimized optical and electrical properties for solar cell applications. Recently, a dramatic increase in the photovoltaic performance of PSCs with organic hole transport materials (HTMs) has been reported. However, as of now, future commercialization can be hampered because the stability of PSCs with organic HTM has not been guaranteed for long periods under conventional working conditions, including moist conditions. Furthermore, conventional organic HTMs are normally expensive because material synthesis and purification are complicated. It is herein reported, for the first time, octadecylamine‐capped pyrite nanoparticles (ODA‐FeS₂ NPs) as a bi‐functional layer (charge extraction layer and moisture‐proof layer) for organo‐lead halide PSCs. FeS₂ is a promising candidate for the HTM of PSCs because of its high conductivity and suitable energy levels for hole extraction. A bi‐functional layer based on ODA‐FeS₂ NPs shows excellent hole transport ability and moisture‐proof performance. Through this approach, the best‐performing device with ODA‐FeS₂ NPs‐based bi‐functional layer shows a power conversion efficiency of 12.6% and maintains stable photovoltaic performance in 50% relative humidity for 1000 h. As a result, this study has the potential to break through the barriers for the commercialization of PSCs.     

Heteroatom Effect on Star‐Shaped Hole‐Transporting Materials for Perovskite Solar Cells

Three new star‐shaped hole‐transporting materials (HTMs) incorporating benzotripyrrole, benzotrifuran, and benzotriselenophene central cores endowed with three‐armed triphenylamine moieties ( BTP‐1 , BTF‐1 , and BTSe‐1 , respectively) are designed, synthesized, and implemented in perovskite solar cells (PSCs). The impact that the heteroatom‐containing central scaffold has on the electrochemical and photophysical properties, as well as on the photovoltaic performance, is systematically investigated and compared with their sulfur‐rich analogue ( BTT‐3 ). The new HTMs exhibit suitable highest‐occupied molecular orbitals (HOMO) levels regarding the valence band of the perovskite, which ensure efficient hole extraction at the perovskite/HTM interface. The molecular structures of BTF‐1 , BTT‐3 , and BTSe‐1 are fully elucidated by single‐crystal X‐ray crystallography as toluene solvates. The optimized (FAPbI₃)_0.85(MAPbBr₃)_0.15‐based perovskite solar cells employing the tailor‐made, chalcogenide‐based HTMs exhibit remarkable power conversion efficiencies up to 18.5%, which are comparable to the devices based on the benchmark spiro‐OMeTAD. PSCs with BTP‐1 exhibit a more limited power conversion efficiency of 15.5%, with noticeable hysteresis. This systematic study indicates that chalcogenide‐based derivatives are promising HTM candidates to compete efficiently with spiro‐OMeTAD.     

Fully High‐Temperature‐Processed SnO2 as Blocking Layer and Scaffold for Efficient,Stable, and Hysteresis‐Free Mesoporous Perovskite Solar Cells

Planar perovskite solar cells (PSCs) based on low‐temperature‐processed (LTP) SnO₂ have demonstrated excellent photovoltaic properties duo to the high electron mobility, wide bandgap, and suitable band energy alignment of LTP SnO₂. However, planar PSCs or mesoporous (mp) PSCs based on high‐temperature‐processed (HTP) SnO₂ show much degraded performance. Here, a new strategy with fully HTP Mg‐doped quantum dot SnO₂ as blocking layer (bl) and a quite thin SnO₂ nanoparticle as mp layer are developed. The performances of both planar and mp PSCs has been greatly improved. The use of Mg‐SnO₂ in planar PSCs yields a high‐stabilized power conversion efficiency (PCE) of close to 17%. The champion of mp cells exhibits hysteresis free and stable performance with a high‐stabilized PCE of 19.12%. The inclusion of thin mp SnO₂ in PSCs not only plays a role of an energy bridge, facilitating electrons transfer from perovskite to SnO₂ bl, but also enhances the contact area of SnO₂ with perovskite absorber. Impedance analysis suggests that the thin mp layer is an “active scaffold” selectively collecting electrons from perovskite and can eliminate hysteresis and effectively suppress recombination. This is an inspiring advance toward high‐performance PSCs with HTP mp SnO₂.     

Dopant‐Free Spiro‐Triphenylamine/Fluorene as Hole‐Transporting Material for Perovskite Solar Cells with Enhanced Efficiency and Stability

Chemical doping is often used to enhance electric conductivity of the conjugated molecule as hole‐transporting material (HTM) for the application in optoelectronics. However, chemical dopants can promote ion migration at the electrical field, which deteriorates the device efficiency as well as increases the fabrication cost. Here, two star HTMs, namely 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenyl‐amine) 9,9′‐spirobifluorene (Spiro‐OMeTAD) and poly(triarylamine) are subjeted to chemical combination to yield dopant‐free N2,N2,N2′,N2′,N7,N7,N7′,N7′‐octakis(4‐methoxyphenyl)‐10‐phenyl‐10H‐spiro[acridine‐9,9′‐fluorene]‐2,2′,7,7′‐tetraamine (SAF‐OMe). The power conversion efficiencies (PCEs) of 12.39% achieved by solar cells based on pristine, dopant‐free SAF‐OMe are among the highest reported for perovskite solar cells and are even comparable to devices based on chemically doped Spiro‐OMeTAD (14.84%). Moreover, using a HTM comprised of SAF‐OMe with an additional dopant results in a record PCE of 16.73%. Compared to Spiro‐OMeTAD‐based devices, SAF‐OMe significantly improves stability.     

Benzodithiophene Hole‐Transporting Materials for Efficient Tin‐Based Perovskite Solar Cells

Developing efficient interfacial hole transporting materials (HTMs) is crucial for achieving high‐performance Pb‐free Sn‐based halide perovskite solar cells (PSCs). Here, a new series of benzodithiophene (BDT)‐based organic small molecules containing tetra‐ and di‐triphenyl amine donors prepared via a straightforward and scalable synthetic route is reported. The thermal, optical, and electrochemical properties of two BDT‐based molecules are shown to be structurally and energetically suitable to serve as HTMs for Sn‐based PSCs. It is reported here that ethylenediammonium/formamidinium tin iodide solar cells using BDT‐based HTMs deliver a champion power conversion efficiency up to 7.59%, outperforming analogous reference solar cells using traditional and expensive HTMs. Thus, these BDT‐based molecules are promising candidates as HTMs for the fabrication of high‐performance Sn‐based PSCs.     

Boosting the Efficiency of SnO2‐Triple Cation Perovskite System Beyond 20% Using Nonhalogenated Antisolvent

Solution‐processed triple‐cation perovskite solar cells (PSCs) rely on complex compositional engineering or delicate interfacial passivation to balance the trade‐off between cell efficiency and long‐term stability. Herein, the facile fabrication of highly efficient, stable, and hysteresis‐free tin oxide (SnO₂)‐based PSCs is demonstrated with a champion cell efficiency of 20.06% using a green, halogen‐free antisolvent. The antisolvent, composed of ethyl acetate (EA) solvent and hexane (Hex) in different proportions, works exquisitely in regulating perovskite crystal growth and passivating grain boundaries, leading to the formation of a crack‐free perovskite film with enlarged grain size. The high quality perovskite film inhibits carrier recombination and substantially improves the cell efficiency, without requiring an additional enhancer/passivation layer. Furthermore, these PSCs also demonstrate remarkable long‐term stability, whereby unencapsulated cells exhibit a power conversion efficiency (PCE) retention of ≈71% after >1500 hours of storage under ambient condition. For encapsulated cells, an astounding PCE retention of >98% is recorded after >3000 hours of storage in air. Overall, this work realizes the fabrication of SnO₂‐based PSCs with a performance greater or comparable to the state‐of‐the‐art PSCs produced with halogenated antisolvents. Evidently, EA–Hex antisolvent can be an extraordinary halogen‐free alternative in maximizing the performance of PSCs.     

Low‐Bandgap Mixed Tin‐Lead Perovskites and Their Applications in All‐Perovskite Tandem Solar Cells

Efficient organic–inorganic metal halide perovskite absorbers have gained tremendous research interest in the past decade due to their super optoelectronic properties and defect tolerance. Lead (Pb) halide perovskites enable highly efficient perovskite solar cells (PSCs) with a record power conversion efficiency (PCE) of over 23%. However, the energy bandgaps of Pb halide perovskites are larger than the optimal bandgap for single junction solar cells, governed by the Shockley–Queisser (SQ) radiative limit. Mixed tin (Sn)‐Pb halide perovskites have drawn significant attention, since their bandgap can be tuned to below 1.2 eV, which opens a door for fabricating all‐perovskite tandem solar cells that can break the SQ radiative limit. This review summarizes the development of low‐bandgap mixed Sn‐Pb PSCs and their applications in all‐perovskite tandem solar cells. Its aim is to facilitate the development of new approaches to achieve high efficiency low‐bandgap single‐junction mixed Sn‐Pb PSCs and all‐perovskite tandem solar cells.     

Efficient and Stable Mesoscopic Perovskite Solar Cells Using PDTITT as a New Hole Transporting Layer

Stability is the main challenge in the field of organic–inorganic perovskite solar cells (PSCs). Finding low‐cost and stable hole transporting layer (HTL) is an effective strategy to address this issue. Here, a new donor polymer, poly(5,5‐didecyl‐5H‐1,8‐dithia‐as‐indacenone‐alt‐thieno[3,2‐b]thiophene) (PDTITT), is synthesized and employed as an HTL in PSCs, which has a suitable band alignment with respect to the double‐A cation perovskite film. Using PDTITT, the hole extraction in PSCs is greatly improved as compared to commonly used HTLs such as 2,2′,7,7′‐tetrakis[N,N‐di(4‐methoxyphenyl)amino]‐9,9′‐spirobifluorene (spiro‐OMeTAD), addressing the hysteresis issue. After careful optimization, an efficient PSC is achieved based on mesoscopic TiO₂ electron transporting layer with a maximum power conversion efficiency (PCE) of 18.42% based on PDTITT HTL, which is comparable with spiro‐OMeTAD‐based PSC (19.21%). Since spiro‐based PSCs suffer from stability issue, the operational stability in the PSC with PDTITT HTL is studied. It is found that the device with PDTITT retains 88% of its initial PCE value after 200 h under illumination, which is better than the spiro‐based PSC (54%).     

Double-layered hole transport material of CuInS2/Spiro for highly efficient and stable perovskite solar cells

In this paper, double-layered hole transport material (HTM) was designed and fabricated by adding a thin CuInS₂ film between perovskite and Spiro-OMeTAD (Spiro) layers. The power conversion efficiency (PCE) of the perovskite solar cells (PSCs) with double-layered HTM of CuInS₂/Spiro was improved to 19.63% from 17.97% for the devices with pure Spiro. Moreover, the operational stability of the PSCs with double-layered HTM of CuInS₂/Spiro was enhanced. The PCE of the PSCs with CuInS₂/Spiro retains 91% of the initial value after 30 days storage in ambient atmosphere. The experimental results indicate that the improved performance could be come from the energy band match between CuInS₂ and Spiro, fast hole extraction and transport, and decreased charge recombination in the PSCs with double-layered HTM of CuInS₂/Spiro. This work provides a promising prospect to design a low-cost and high stability HTM for commercial PSCs.     

Self‐Additive Low‐Dimensional Ruddlesden–Popper Perovskite by the Incorporation of Glycine Hydrochloride for High‐Performance and Stable Solar Cells

The recent rise of low‐dimensional Ruddlesden–Popper (RP) perovskites is notable for superior humidity stability, however they suffer from low power conversion efficiency (PCE). Suitable organic spacer cations with special properties display a critical effect on the performance and stability of perovskite solar cells (PSCs). Herein, a new strategy of designing self‐additive low‐dimensional RP perovskites is first proposed by employing a glycine salt (Gly⁺) with outstanding additive effect to improve the photovoltaic performance. Due to the strong interaction between C?O and Pb²⁺, the Gly⁺ can become a nucleation center and be beneficial to uniform and fast growth of the Gly‐based RP perovskites with larger grain sizes, leading to reduced grain boundary and increased carrier transport. As a result, the Gly‐based self‐additive low‐dimensional RP perovskites exhibit remarkable photoelectric properties, yielding the highest PCE of 18.06% for Gly (n = 8) devices and 15.61% for Gly (n = 4) devices with negligible hysteresis. Furthermore, the Gly‐based devices without encapsulation show excellent long‐term stability against humidity, heat, and UV light in comparison to BA‐based low‐dimensional PSCs. This approach provides a feasible design strategy of new‐type low‐dimensional RP perovskites to obtain highly efficient and stable devices for next‐generation photovoltaic applications.     

Improvement and Regeneration of Perovskite Solar Cells via Methylamine Gas Post‐Treatment

The control of film morphology is crucial in achieving high‐performance perovskite solar cells (PSCs). Herein, the crystals of the perovskite films are reconstructed by post‐treating the MAPbI₃ devices with methylamine gas, yielding a homogeneous nucleation and crystallization of the perovskite in the triple mesoscopic inorganic layers structured PSCs. As a result, a uniform, compact, and crystalline perovskite layer is obtained after the methylamine gas post‐treatment, yielding high power conversion efficiency (PCE) of 15.26%, 128.8% higher than that of the device before processing. More importantly, this post‐treatment process allows the regeneration of the photodegraded PSCs via the crystal reconstruction and the PCE can recover to 91% of the initial value after two cycles of the photodegradation‐recovery process. This simple method allows for the regeneration of perovskite solar cells on site without reconstruction or replacing any components, thus prolonging the service life of the perovskite solar cells and distinguishing from any other photovoltaic devices in practice.     

Water‐Soluble Triazolium Ionic‐Liquid‐Induced Surface Self‐Assembly to Enhance the Stability and Efficiency of Perovskite Solar Cells

Despite being a promising candidate for next‐generation photovoltaics, perovskite solar cells (PSCs) exhibit limited stability that hinders their practical application. In order to improve the humidity stability of PSCs, herein, a series of ionic liquids (ILs) “1‐alkyl‐4‐amino‐1,2,4‐triazolium” (termed as RATZ; R represents alkyl chain, and ATZ represents 4‐amino‐1,2,4‐triazolium) as cations are designed and used as additives in methylammonium lead iodide (MAPbI₃) perovskite precursor solution, obtaining triazolium ILs‐modified PSCs for the first time (termed as MA/RATZ PSCs). As opposed to from traditional methods that seek to improve the stability of PSCs by functionalizing perovskite film with hydrophobic molecules, humidity‐stable perovskite films are prepared by exploiting the self‐assembled monolayer (SAM) formation of water‐soluble triazolium ILs on a hydrophilic perovskite surface. The mechanism is validated by experimental and theoretical calculation. This strategy means that the MA/RATZ devices exhibit good humidity stability, maintaining around 80% initial efficiency for 3500 h under 40 ± 5% relative humidity. Meanwhile, the MA/RATZ PSCs exhibit enhanced thermal stability and photostability. Tuning the molecule structure of the ILs additives achieves a maximum power conversion efficiency (PCE) of 20.03%. This work demonstrates the potential of using triazolium ILs as additives and SAM and molecular design to achieve high performance PSCs.     

FAPbI3 Flexible Solar Cells with a Record Efficiency of 19.38% Fabricated in Air via Ligand and Additive Synergetic Process

Compared with silicon‐based solar cells, organic–inorganic hybrid perovskite solar cells (PSCs) possess a distinct advantage, i.e., its application in the flexible field. However, the efficiency of the flexible device is still lower than that of the rigid one. First, it is found that the dense formamidinium (FA)‐based perovskite film can be obtained with the help of N‐methyl‐2‐pyrrolidone (NMP) via low pressure‐assisted method. In addition, CH₃NH₃Cl (MACl) as the additive can preferentially form MAPbCl_3?xI_x perovskite seeds to induce perovskite phase transition and crystal growth. Finally, by using FAI·PbI₂·NMP+x%MACl as the precursor, i.e., ligand and additive synergetic process, a FA‐based perovskite film with a large grain size, high crystallinity, and low trap density is obtained on a flexible substrate under ambient conditions due to the synergetic effect, e.g., MACl can enhance the crystallization of the intermediate phase of FAI·PbI₂·NMP. As a result, a record efficiency of 19.38% in flexible planar PSCs is achieved, and it can retain about 89% of its initial power conversion efficiency (PCE) after 230 days without encapsulation under ambient conditions. The PCE retains 92% of the initial value after 500 bending cycles with a bending radii of 10 mm. The results show a robust way to fabricate highly efficient flexible PSCs.     

Near‐Infrared Small Molecule Acceptor Enabled High‐Performance Nonfullerene Polymer Solar Cells with Over 13% Efficiency

One of the most promising approaches to achieve high‐performance polymer solar cells (PSCs) is to develop nonfullerene small molecule acceptors (SMAs) with an absorption extending to the near‐infrared (NIR) region. In this work, two novel SMAs, namely, BTTIC and BTOIC, are designed and synthesized, with optical bandgaps (E_g^opt) of 1.47 and 1.39 eV, respectively. Desipte the narrow E_g^opt, the PBDB‐T:BTTIC‐ and PBDB‐T:BTOIC‐based PSCs can maintain high V_OCs of over 0.90 and 0.86 V, respectively, with low energy losses (E_loss) < 0.6 eV. Meanwhile, due to the favorable morphology of the PBDB‐T:BTTIC blend, balanced carrier mobilities are achieved. The high external quantum efficiencies enable a high power conversion efficiency (PCE) up to 13.18% for the PBDB‐T:BTTIC‐based PSCs. In comparison, BTOIC shows an excessive crystallization propensity owing to its oxyalkyl side groups, which eventually leads to a relatively low PCE for the PBDB‐T:BTOIC‐based PSCs. Overall, this work provides insights into the design of novel NIR‐absorbing SMAs for nonfullerene PSCs.     

Achieving 20% Efficiency for Low‐Temperature‐Processed Inverted Perovskite Solar Cells

Low‐temperature‐processed inverted perovskite solar cells (PVSCs) attract increasing attention because they can be fabricated on both rigid and flexible substrates. For these devices, hole‐transporting layers (HTLs) play an important role in achieving efficient and stable inverted PVSCs by adjusting the anodic work function, hole extraction, and interfacial charge recombination. Here, the use of a low‐temperature (≤150 °C) solution‐processed ultrathin film of poly[(9,9‐dioctyl‐fluorenyl‐2,7‐diyl)‐co‐(4,4′‐(N‐(4‐secbutylphenyl) diphenylamine)] (TFB) is reported as an HTL in one‐step‐processed CH₃NH₃PbI₃ (MAPbI₃)‐based inverted PVSCs. The fabricated device exhibits power conversion efficiency (PCE) as high as 20.2% when measured under AM 1.5 G illumination. This PCE makes them one of the MAPbI₃‐based inverted PVSCs that have the highest efficiency reported to date. Moreover, this inverted PVSC also shows good stability, which can retain 90% of its original efficiency after 30 days of storage in ambient air.