Perovskite Precursor Research Articles

Self-Powered Wide-Narrow Bandgap-Laminated Perovskite Photodetector with Bipolar Photoresponse for Secure Optical Communication.

Perovskite photodetectors with bipolar photoresponse characteristics are expected to be applied in the field of secure optical communication (SOC). However, how to realize the perovskite photodetector with bipolar response remains challenging. Herein, by introducing bismuth iodide (BiI3 ) into Sn-Pb mixed perovskite precursor solution, 2D perovskite FA3 Bi2 I9 is spontaneously formed at the bottom to realize a wide-narrow bandgap-laminated perovskite film. Wavelength-dependent bipolar response is realized based on the absorption difference of the photoactive region with different bandgap combined with the carrier competition of the homotypic transport layer adopted in the as-fabricated photodetector. Under the visible/near-infrared (NIR) light irradiation, the bottom/top of the film generates a higher carrier concentration, where electrons are easier to be separated and transported by the SnO2 /PC61 BM to the bottom/top electrodes, respectively, resulting in a negative and positive bipolar response. Finally, based on positive NIR signal as the effective signal and negative visible signal as the interference signal, the SOC system is realized, where the positive NIR signal is well hidden by the negative visible signal. This work provides a simple and feasible strategy for fabrication of laminated perovskite films to achieve bipolar response.

Ionic surfactants of different dipole moments as anti-solvent additives for air-processing MAPbI3−xClx perovskite thin films

Three ionic surfactants, didodecyldimethylammonium bromide (DDABr), sodium lauryl ether sulfate (NaLES) and sodium lauryl sulfate (NaLS), with different dipole moment values: 0.907, 17 and 212 Debye, respectively, have been used as anti-solvent additives to remove the moisture from perovskite precursor solutions. The three additives impact in different ways on the crystallinity, wettability and morphology of perovskite thin films, as well as on the stability and efficiency of air-processed perovskite solar cells (PSCs). The hydrophobic groups of the additives at the surface of perovskite thin films help to increase the stability of PSCs, especially DDABr of the lowest dipole moment. On the other hand, NaLES, of the highest dipole moment, is the most efficient to extract moisture from the perovskite precursor coatings, increasing the average power conversion efficiency (PCE) of NaLES-based PSCs from 16.16 ± 0.94% to 17.21 ± 0.32% in comparison with that of the reference. Furthermore, the synergy between NaLES and the perovskite precursor additive, KI, achieves the best photovoltaic performance of the PSCs, leading to an average PCE of 17.42% and the best PCE of 18.75%. It is concluded that ionic surfactants of different dipole moments are good candidates as anti-solvent additives to improve the efficiency and stability of air-processed PSCs.

Solution-processed lead-free cesium titanium halide perovskites and their structural and optical characteristics

Two primary challenges impede the extensive utilization of organic-inorganic lead halide perovskites: instability and potential risk of lead contamination. This paper describes an easy and effective solution-phase method for synthesizing lead-free Cs2TiI6 perovskites using inverse temperature crystallization. The perovskite precursor was deposited on glass substrates using various methods. The Cs2TiI6 films exhibit a cubic structure with a lattice parameter of 11.57 Å. The drop-cast thin film exhibited strong and broad absorption in the visible spectrum, indicating that Cs2TiI6 possesses notable optical properties. The optical energy gap calculated for both direct and indirect is 1.68 eV and 1.65 eV, respectively). The refractive index and optical conductivity demonstrate that Cs2TiI6 is an excellent optical absorber for photodevices. This study offers valuable perspectives for the advancement of lead-free double perovskites.

Comprehensive Crystal Regulation Reduces Interfacial Energy Loss for Efficient Blue Perovskite Light-Emitting Diodes.

As an essential component of future full-color displays, blue perovskite light-emitting diodes (PeLEDs) still lag far behind the red and green counterparts in the device performances. In the mainstream quasi-2D blue perovskite system, trap-mediated nonradiative loss, low energy transfer efficiency, and interface fluorescence quenching remain significant challenges. Herein, guanidinium thiocyanate (GASCN) and potassium cinnamate (PCA) are respectively introduced into the hole transport layer (HTL) and the perovskite precursor to achieve a dense and uniform perovskite thin film with greatly improved optoelectronic properties. Therefore, adequate GA+ acts as pre-nucleation sites on the HTL surface, regulating crystallization through strong hydrogen bonding with perovskite intermediates. The realized polydisperse domain distribution is conducive to cascade energy transfer, and the improved hole transport ability alleviates interface fluorescence quenching. In addition, the SCN- and CA- groups can form coordination bonds with the defects at the buried perovskite interface and grain boundaries, respectively, which effectively suppresses the detrimental nonradiative recombination. Benefitting from the comprehensive crystal regulation, blue PeLEDs featuring stable emission at 484 and 468nm exhibit improved external quantum efficiencies of 11.5% and 4.3%, respectively.

Significant Efficiency and Stability Enhancement of Flexible Perovskite Solar Cells Combining with Multifunctional Effects of a Natural Spice

AbstractThe numerous defect‐induced non‐radiative recombination losses and residual stress in the preparation of perovskite film greatly hinder the further improvement of the efficiency and stability of flexible perovskite solar cells (PSCs). Here, a natural spice 7‐amino‐4‐(trifluoromethyl)‐2‐benzopyrone (ATB) containing amino (─NH2), carbonyl (─C═O), and trifluoromethyl (─CF3) functional groups is introduced into the perovskite precursor solution, thereby preparing high‐quality perovskite film with low defect density. It is revealed that the utilization of ATB is beneficial to comprehensively passivate the defects and release the residual stress of perovskite film through the synergistic effect of functional groups, thereby improving the crystallinity and enhancing the carrier lifetime of perovskite film. Moreover, the introduction of ATB contributes to an improved energy levels alignment between the perovskite and adjacent layers, which facilitates fast carrier transport and suppresses the recombination loss in the flexible PSCs. Combined with the multifunctional effects of ATB, the target flexible and rigid PSCs with ATB modification yield remarkable photoelectric conversion efficiency (PCE) of 21.08% and 23.79%, respectively. More importantly, the ATB‐modified flexible device exhibits outstanding stability and retains 87.3% and 91.6% of the original efficiency after aging for 3000 h at 50 ± 5 relative humidity and 5000 bending cycles, respectively.

Additive Engineering of Imidazolium-based cation for defect passivation with enhanced performance and stability of carbon-based perovskite solar cells

Due to the rapid increase in the power conversion efficiency (PCE) of perovskite solar cells (PSCs) and approaching the theoretical maximum level in recent years, the main drawback of their future commercialization is to improve their long-term stability under existing environmental conditions. One of the problems with this technology lies in the absorbing layer, specifically the perovskite. In particular, when producing a perovskite film under ambient conditions, it is almost impossible to avoid film defects caused by environmental conditions (such as moisture, oxygen, and temperature), which could randomly change during the preparation process. Therefore, the fabrication of high-quality perovskite films is an urgent process that has a direct impact on the overall performance of the solar cells. The use of ionic liquids (ILs) as additives in perovskite precursor solutions is a promising strategy to improve not only the power conversion efficiency (PCE) but also the long-term stability of photovoltaic devices by controlling nucleation and crystal growth of perovskite film that avoids defects and produces high-quality perovskite layers. Here, the critical role of the ionic liquid 1-methyl-3-propylimidazolium iodide (1-MPII) in different perovskite precursor solutions such as MAPbI3 (I), MAPbI3-PbBr2 (B) and MAPbI3-PbCl2 (CL) on carbon-based perovskite solar cells (C–PSCs) under ambient conditions is extensively studied. The results show that 1-MPII ionic liquid activates the surface morphology of all perovskite films and improves solar cells’ efficiency due to the passivation of the uncoordinated Pb2+ defects. Furthermore, stability measurements show that the unencapsulated IL-modified devices for perovskites MAPbI3 (IIL), MAPbI3-PbBr2 (BIL), and MAPbI3-PbCl2 (CLIL) retained at 84 %, 86 %, and 80 % of their original PCE for over 1100 h under ambient conditions with 45 % relative humidity (RH), compared to the IL-free PSCs. Moreover, the IL-modified PSCs exhibited an increased electrical performance ranging from 16.5 % to 33 % depending on the type of perovskite it was used, so that long-term stability also was reinforced.

Regulating Crystal Orientation via Ligand Anchoring Enables Efficient Wide-Bandgap Perovskite Solar Cells and Tandems.

Wide-bandgap (WBG) perovskite solar cells have attracted considerable interest for their potential applications in tandem solar cells. However, the predominant obstacles impeding their widespread adoption are substantial open-circuit voltage (VOC ) deficit and severe photo-induced halide segregation. To tackle these challenges, a crystal orientation regulation strategy by introducing dodecyl-benzene-sulfonic-acid as an additive in perovskite precursors is proposed. This method significantly promotes the desired crystal orientation, passivates defects, and mitigates photo-induced halide phase segregation in perovskite films, leading to substantially reduced nonradiative recombination, minimized VOC deficits, and enhanced operational stability of the devices. The resulting 1.66eV bandgap methylamine-free perovskite solar cells achieve a remarkable power conversion efficiency (PCE) of 22.40% (certified at 21.97%), with the smallest VOC deficit recorded at 0.39V. Furthermore, the fabricated semitransparent WBG devices exhibit a competitive PCE of 20.13%. Consequently, four-terminal tandem cells comprising WBG perovskite top cells and 1.25eV bandgap perovskite bottom cells showcase an impressive PCE of 28.06% (stabilized 27.92%), demonstrating great potential for efficient multijunction tandem solar cell applications.

HIGHLY STABLE PEROVSKITE FILM WITH IONIC LIQUID ADDITIVES FOR AMBIENT AIR DEPOSITION

Perovskite solar cells (PSCs) technology has emerged as a highly promising photovoltaic (PV) option due to remarkable advancements in power conversion efficiency (PCE). Nevertheless, the stability of PSCs continues to pose a challenge for commercialization, as factors such as moisture, oxygen, light, and temperature can lead to degradation during fabrication and actual use stage. The stability of the perovskite film is crucial for extending the device’s lifetime and performance. This research seeks to explore the degradation mechanism and improve the perovskite film’s stability by incorporating 1-butyl-3-methylimidazolium tetrafluoroborate (BMIMBF4) and 1,3-dimethyl-3-imidazolium hexafluorophosphate (DMIMPF6) ionic liquids into a perovskite precursor using the two-step deposition technique in ambient air. The perovskite film’s degradation and PSCs’ stability were evaluated under high relative humidity conditions, averaging 73%RH without encapsulation. UV-visible spectroscopy results indicate that the most stable perovskite film, containing the BMIMBF4 ionic liquid additive, maintains its α phase perovskite structure for 144 hours without alterations in absorbance and persisted for over 336 hours before degrading into an undesirable δ phase perovskite. Furthermore, PSCs retained 74.1% of their initial PCE after 28 days of exposure to ambient conditions. This research offers promising findings for the large-scale fabrication of stable PSCs.

Post-Treatment-Free Dual-Interface Passivation via Facile 1D/3D Perovskite Heterojunction Construction.

For achieving high-efficiency perovskite solar cells, it is almost always necessary to substantially passivate defects and protect the perovskite structure at its interfaces with charge transport layers. Such a modification generally involves the post-treatment of the deposited perovskite film by spin coating, which cannot meet the technical demands of scaling up the production of perovskite photovoltaics. In this work, we demonstrate one-step construction of buried and capped double 1D/3D heterojunctions without the need for any post-treatment, which is achieved through facile tetraethylammonium trifluoroacetate (TEATFA) prefunctionalization on the SnO2 substrate. The functional TEATFA salt is first deposited onto the SnO2 substrate and reacts on this buried interface. Once the FAPbI3 perovskite precursor solution is dripped, a portion of the TEA+ cations spontaneously diffuse to the top surface over film crystallization. The TEATFA-based water-resistant 1D/3D TEAPbI3/FAPbI3 heterojunctions at both the buried and capped interfaces lead to much better photovoltaic performance and higher operational stability. Since this approach saves the need for any postsynthesis passivation, its feasibility for the fabrication of large-area perovskite photovoltaics is also showcased. Compared to ∼15% for a pristine 5 cm × 5 cm FAPbI3 mini-module without postsynthesis passivation, over 20% efficiency is achieved following the proposed route, demonstrating its great potential for larger-scale fabrication with fewer processing steps.

Aging‐Resistant Precursor with Ultrawide Annealing Window for 24.08% Perovskite Solar Cells

AbstractPerovskite solar cells (PSCs) have attracted extensive attention in the photovoltaic field, with their highest power conversion efficiency (PCE) reaching 26%. However, the commercialization of PSCs is severely hindered by the instability of precursor solutions and the narrow annealing window for perovskite films. Here, 2,3,5‐trichlorobenzaldehyde (3Cl‐BZH) is introduced into the organic salt precursor solution to eliminate excess organic amines through Schiff‐base reactions, avoiding subsequent irreversible amine‐cation reaction of formamidine‐methylammonium (FA‐MA+) and improve the stability of the precursor solution. Meanwhile, the chemical interaction between C═O group of 3Cl‐BZH and formamidinium (FA+) in the perovskite precursor contributes to the slow release of organic ions, which reduces the reaction rate between organic salt and PbI2, retarding the crystallization of perovskite film. The PSCs with a conventional annealing process achieve a champion efficiency of 24.08%, which derives from the defect passivation effect of 3Cl‐BZH. The PSCs with an ultrawide annealing window of 240 h for wet perovskite film in the air still maintain an efficiency of 22.01%. The aging‐resistant precursor and ultrawide annealing window are beneficial for reproducible, efficient, and low‐cost PSCs, which brings great prospects for the commercialization of PSCs.

Room‐Temperature Molten Salt‐Mediated CsPbI3 Growth for Excellent Photovoltaic Performance

AbstractDefects within perovskite have been known to act as the nonradiative recombination centers, negatively impacting the carrier transport, which degrades the photovoltaic performance of perovskite solar cells (PSCs). Therefore, preparing a high‐quality perovskite film is of vital significance. To this end, a room‐temperature molten salt, dimethylamine formate (DMAFa), is introduced into perovskite precursor solution to regulate the crystallization process of CsPbI3 films. DMAFa can coordinate with Pb2+ as HCOO−‐Pb2+ in the early stages, then HCOO−‐Pb2+ is gradually displaced by I−‐Pb2+ due to its decomposition during the subsequent annealing, thus delaying the crystallization rate, meanwhile, the DMA+ can interact with the uncoordinated Pb2+ to passivate defects of perovskite films, thereby, forming a high‐quality CsPbI3 film with large grain size and low‐defect density. As a result of this strategy, the power conversion efficiency is increased to 20.40%, and the open‐circuit voltage is up to 1.21 V. These findings indicate that the introduction of DMAFa offers a fundamental way to achieve high‐performance CsPbI3 PSCs.

Compound doping enables efficient CsPbBr3 nanocrystal light emitting diodes

All-inorganic cesium-based perovskite nanocrystals (PeNCs) attract much attentions in displays due to their facile synthesis protocol and superior luminous performance, while material instability hinders their practical applications. Herein, by inducing a multi-functional dopant, i.e., SrBr2, into the perovskite precursor solution, the as-formed SrBr2-doped CsPbBr3 NCs possess purer phases, suppressed defects and hydrophobic surfaces, which leads to a high photoluminescence quantum yield of ∼90 %, as well as much improved moisture stability. Benefiting from dopant passivation and improved luminescence properties, the doped CsPbBr3 light emitting diodes show five times and two times of current efficiency and external quantum efficiency improvements, respectively, in comparison to their undoped counterparts.

Enhancing the Performance and Stability of Perovskite Solar Cells through the Introduction of the Multifunctional Additive 5‐Amino‐2‐Fluorobenzoic Acid

As the evolution of energy resources continues, perovskite solar cells (PSCs) are gaining increasing attention from researchers and are emerging as strong competitors to silicon‐based solar cells. However, due to the preparation process, defects are inevitable and have a significant impact on the efficiency and stability of PSCs. Therefore, it is essential to explore effective passivation strategies to minimize nonradiative recombination, enhance carrier mobility, and improve the overall photovoltaic performance of these cells. Herein, 5‐amino‐2‐fluorobenzoic acid (5‐AFA) is incorporated into the perovskite precursor solution as an additive. The aim is to investigate the passivation mechanism of the composite, which involves multifunctional groups such as –COOH, –NH2, and –F. The results demonstrate that this additive effectively passivates the defects, suppresses nonradiative recombination, slows down the crystallization process, improves film crystallinity, and ultimately enhances both the efficiency and stability of the PSCs. Specifically, the passivated PSCs achieve an impressive power conversion efficiency of 20.37%. These cells also exhibit remarkable stability with the unencapsulated devices maintaining an initial efficiency of 79% even after 700 h in an indoor environment. These findings highlight the successful application of the 5‐AFA additive in enhancing the performance and durability of PSCs.

Optical enhancement in perovskite thin films using moth-eye anti-reflection film

Perovskite solar cells represent an emerging photovoltaic technology. With the latest record efficiencies exceeding 25% coupled with low fabrication cost and tunable transparency, perovskite solar cells demonstrate promising applications as solar windows. For these applications, the perovskite solar cells need to be semi-transparent to allow incident light to pass through the windows while generating electricity. However, semi-transparency compromises light absorption in the solar cells. In this work, optical enhancement in perovskite thin films using moth-eye anti-reflection (AR) film is investigated. Perovskite thin films with different thicknesses are used and the thickness is controlled by varying the spin speeds during the deposition of the perovskite precursor. The optical effects in the perovskite films without and with moth-eye AR film are studied. From the findings, the reflection loss is reduced by maximum of ∼4%, which contributes to a higher light absorption in the perovskite layer, due to the AR effect of the moth-eye structure. These results imply that the moth-eye film can be a promising and facile alternative for developing a highly efficient and semi-transparent perovskite solar cell with a thin absorber layer.

Crystallization Enhancement and Ionic Defect Passivation in Wide‐Bandgap Perovskite for Efficient and Stable All‐Perovskite Tandem Solar Cells

AbstractBy integrating wide‐bandgap (WBG) and narrow‐bandgap perovskites, monolithic all‐perovskite tandem solar cells have garnered significant attention as a prospective strategy for surpassing the efficiency limits of single‐junction cells. However, the WBG subcells, which significantly impact the performance and operational stability of all‐perovskite tandem solar cells, face notable challenges associated with pronounced nonradiative recombination losses and limited film photostability. Here, an efficient method is reported by adding potassium hypophosphite into the perovskite precursor solution to simultaneously regulate crystallization and passivate ionic defects in WBG perovskites. This approach results in high‐quality perovskite films and significantly improves the performance and photostability of WBG perovskite solar cells. The single‐junction devices with a 1.79 eV bandgap achieve a champion power conversion efficiency (PCE) of 20.06% with an open‐circuit voltage of 1.32 V. The devices retain ≈96% of their initial PCE following 913 h of continuous AM 1.5 G illumination. With these WBG perovskite subcells, monolithic all‐perovskite tandem solar cells are fabricated with an efficiency of 26.08%.

Mechanism of defect passivation achieved by chemical interaction in inverted perovskite solar cells

A variety of defects exist in the solution-processed polycrystalline perovskites, resulting in photovoltaic output losses and degradation. Chemical interaction is a promising way to realize the passivation of defects. Herein, cetyl pyridinium bromide (CPB) containing both pyridine units and long-chain alkyl groups was introduced in the perovskite precursor solution as a passivation agent. Experimental results show that pyridine unit in CPB formed coordination with uncoordinated Pb2+, which also interact with N–H in MAPbI3. Meanwhile, long-chain alkyl groups in CPB had interaction with MAI and PbI2 in MAPbI3. Thus, trace amount of CPB in the precursor solution improved the optoelectronic properties of perovskite films and suppressed non-radiative carrier recombination in perovskite solar cell (PSC). CPB-modified perovskite films exhibit a lower trap-state density and stronger carrier migration capability. It enables the significant enhancement of PCE values of the p-i-n structured PSC from 18.27 % to 20.53 %, accompanied by the improved stability. Our work exhibits more possibility between passivating additive and PSC performance.

Effective of l-tyrosine hydrochloride on the photovoltaic performance of tin-based perovskite solar cells by suppressing tin (II) oxidation

Additive engineering has been widely concerned to improve the photovoltaic performance of tin-based perovskite solar cells (PSCs). Here, the tin-based perovskite precursor solution is modified with L-Tyrosine hydrochloride (LTHCl). The results demonstrate that the defect state density of tin-based perovskite films is reduced by improving their morphology and crystallinity. The electrical properties of tin-based perovskite film are enhanced by suppressing the Sn2+ oxidation. As a result, the open-circuit voltage of tin-based PSCs is increased from 0.53 V to 0.59 V. The best power conversion efficiency of the tin-based PSC with LTHCl is up to 8.63 %, which is higher than that of the pristine device (7.65 %). Meanwhile, the tin-based PSC with LTHCl retains 84 % of its initial efficiency after over 1140 h in a nitrogen glove box.

Tailoring Crystallization Dynamics of CsPbI3 for Scalable Production of Efficient Inorganic Perovskite Solar Cells

AbstractAll‐inorganic perovskite cesium lead triiodide (CsPbI3) with inorganic nature, low‐temperature synthesis, and a suitable bandgap is desirable for high‐performance photovoltaics. However, the scalable production of CsPbI3 photovoltaics is still challenging due to a large nucleation energy barrier and slow phase transition during unassisted natural crystallization. Here, the crystallization dynamics of CsPbI3 thin films is tailored via lead acetate (PbAc2) substitution in the perovskite precursor ink, allowing the scalable fabrication of efficient all‐inorganic perovskite solar cells and minimodules. Introducing PbAc2 enlarges CsPbI3 colloid size in the precursor and reduces the nucleation energy barrier. Additionally, reactions between acetate and dimethylammonium in the wet film accelerate the removal of dimethylammonium additives and generate solvent vapors for self‐regulate internal solvent annealing, resulting in densely packed, uniform, and pinhole‐free CsPbI3 perovskite films over large areas. This strategy demonstrates inverted CsPbI3 solar cells with 20.17% efficiency and good operational stability (retaining 95.5% of initial efficiency after continuous operation for 1800 h) and 15.1%‐efficient CsPbI3 minimodules with an active area of 26.8 cm2.

Surface modification of paper substrates by a printed UV curing varnish layer and a transferred transparent PEDOT:PSS electrode for paper-based perovskite light-emitting devices in ambient air

Paper, a low-cost and eco-friendly substrate, can be used to prepare flexible electronic devices by resorting to surface modification technology. In this study, we investigated the surface modification of paper substrates, including those that were uncoated or coated with traditional mineral coatings, to analyze the enhancements to surface flatness and water resistance using a UV curing varnish layer. Furthermore, we explored the formation of perovskite films on the surface-modified paper substrates utilizing a PEO-doped perovskite precursor solution in ambient air, and the surface morphology, crystallinity, photoluminescence properties, and absorption properties of the prepared perovskite films were discussed accordingly. Considering the nontransparent feature of paper-based substrates, the inverted perovskite light-emitting device was finally assembled by transfer printing a transparent PEDOT:PSS layer as a top electrode. The conductive and optical properties of the electrode layer were thus analyzed as well. It is found that the surface modification of paper substrates via printing the UV curing varnish can illustrate significant improvements, such as pore-filling on the surface, a more than 10-fold reduction in roughness, and downward penetration. Moreover, prepared perovskite films on the surface-modified coated paper exhibit superior enhancements, including photoluminescence, higher crystallinity, and surface roughness and porosity. Devices fabricated on the surface-modified substrates are less susceptible to short-circuiting. The electroluminescence on the surface-modified coated paper substrate is 2.16 times higher than the prepared device on the surface-modified base paper substrate and even 3.23 times higher than on the PET substrate. Therefore, it is quite feasible to fabricate a perovskite light-emitting device on the modified surface of a paper substrate by using a printed UV curing varnish layer, which is expected to be a promising coating to polish the paper surface in the preparation of electroluminescent devices.

Anion-π interactions suppress phase impurities in FAPbI3 solar cells.

Achieving both high efficiency and long-term stability is the key to the commercialization of perovskite solar cells (PSCs)1,2. However, the diversity of perovskite (ABX3) compositions and phases makes it challenging to fabricate high-quality films3-5. Perovskite formation relies on the reaction between AX and BX2, whereas most conventional methods for film-growth regulation are based solely on the interaction with the BX2 component. Herein, we demonstrate an alternative approach to modulate reaction kinetics by anion-π interaction between AX and hexafluorobenzene (HFB). Notably, these two approaches are independent but work together to establish 'dual-site regulation', which achieves a delicate control over the reaction between AX and BX2 without unwanted intermediates. The resultant formamidinium lead halides (FAPbI3) films exhibit fewer defects, redshifted absorption and high phase purity without detectable nanoscale δ phase. Consequently, we achieved PSCs with power conversion efficiency (PCE) up to 26.07% for a 0.08-cm2 device (25.8% certified) and 24.63% for a 1-cm2 device. The device also kept 94% of its initial PCE after maximum power point (MPP) tracking for 1,258 h under full-spectrum AM 1.5 G sunlight at 50 ± 5 °C. This method expands the range of chemical interactions that occur in perovskite precursors by exploring anion-π interactions and highlights the importance of the AX component as a new and effective working site to improved photovoltaic devices with high quality and phase purity.