Power Conversion Efficiency Of Perovskite Solar Cells Research Articles

In Situ PL Probes the Effect of 2D SnSe Nanosheets on the Crystallization Process of CsPbI2Br Perovskite Solar Cells.

Reducing defects in the active layer is important for improving the crystalline quality of all-inorganic perovskite solar cells (PSCs). Exploring novel additives is one of the most promising approaches to minimize active layer defects. In this work, two-dimensional (2D) SnSe nanosheets with excellent optoelectronic properties are prepared using an ultrasonic exfoliation method. The prepared 2D SnSe nanosheets are introduced into a CsPbI2Br precursor, which reduces the defect formation at grain boundaries and enhances the crystallinity of CsPbI2Br perovskites. We use the in situ photoluminescence (PL) technique to investigate the role of 2D materials in the crystallization process. The results show that SnSe nanosheets primarily shorten the grain boundary merging time and reduce the defect generation during the grain boundary merging stage, thereby regulating the crystallization of perovskite. In addition, SnSe nanosheets passivate uncoordinated Pb atoms at grain boundaries by Se atoms, further reducing the defect density in perovskite. As a result, PSCs exhibit a higher power conversion efficiency (PCE) of 14.24% and a Voc of 1.22 V. This study highlights the role of 2D materials in enhancing the crystalline quality and PCE of PSCs.

Temperature-assisted crystallization and morphology for CH3NH3PbI3 perovskite solar cells using laser-induced heat treatment

In this study, perovskite solar cells (PSCs) were fabricated using a two-step solution deposition method. A laser beam was applied at the interface between lead iodide (PbI2) and methylammonium iodide to change the reaction temperature and stimulate the growth of perovskite crystals. A notable enhancement was observed in the power conversion efficiency of PSCs. The laser scanning speed was investigated to control the reaction temperature and further control the crystallization and morphology of the perovskite film. Based on the optimized laser scanning speed, the best and average PCEs obtained were 14.33 % and 13.92 ± 0.52 %, respectively, which were higher than those achieved using the conventional technique (12.18 % and 11.37 ± 0.74 %, respectively) and the conventional heating methods (14.09 % and 13.28 ± 0.56 %, respectively). The optimal reaction temperature at the interface was predicted to be 80 °C under optimized conditions using the COMSOL software. This study will help in scaling this technique for large–area PSCs, optimizing the laser parameters for different perovskite compositions, and investigating the long-term stability of enhanced PSCs, boosting their commercial viability.

Incorporation of Small Molecules with Polar Functional Group to Elevate Crystallinity and Suppress Nonradiative Recombination in Perovskite Solar Cells

To get maximum efficiency, potential in perovskite solar cells (PSCs) has made it hot research area now a days. Power conversion efficiency of PSCs is increasing by every passing day. Moreover, performance of perovskite absorber layer is important for high efficiency andlong term stability of PSCs. In this work, 2‐4 (Methyl sulphonyl) Phenyl) Ethylamine small molecules with functional groups are added inperovskite and enlarged grains are observed in the result. These effects show improvement in the performance of perovskite. Consequently, density of imperfections with additive in PSCs is alleviated and champion efficiency 24.16% has been achieved. Within corporation of additive with polar functional group crystallinity of absorber film is increased, that is confirmed by X‐ray diffraction and Uv‐Vis results. PL result show absorption is increased with addition ofadditive due to mitigation of nonradiative charge recombination. It is confirmed by GIWAX that charge transportation is increased since output peakintensity for (100) plane is larger than that of input. Overall, efficiencyis increased from 22% for control and exceeding 24% and stability enhanced with incorporation of small molecules.

Comparative life cycle assessment of integrated renewable energy-based power systems

Integrated renewable-based power cycles should be employed to produce more sustainable electricity. This is a comparative life cycle assessment (LCA) of three combined power plants, encompassing: case 1 involving combined geothermal and wind, case 2 featuring combined geothermal and solar, and case 3 integrating wind and solar systems. The base case perovskite solar cell (PSC) modelling assumes a 3-year lifespan and a power conversion efficiency of 17 %. However, diverse scenarios are evaluated through a sensitivity assessment involving enhancements in lifetime and efficiency. The base case evaluation emphasizes that the phases with the most significant negative environmental effects which includes the drilling of geothermal wells, construction of wind plants, and manufacturing and installation of PSCs. The midpoint findings indicate that boosting the power conversion efficiency of PSC from 17 % to 35 % yields a notable decrease in environmental impact. Moreover, extending the lifetime from 3 to 15 years led to reduction in CO2 emissions from 0.0373 and 0.0185 kg CO2 eq/kWh to 0.026 and 0.0079 kg CO2 eq/kWh in cases 2 and 3, respectively. Assessing worst and best-case scenarios highlights significant declines in certain impact categories. In case 3, terrestrial ecotoxicity (TE), photochemical oxidant formation (POF), human toxicity (HT), marine ecotoxicity (ME), and marine eutrophication (MU) saw reductions exceeding 88 % compared to worst-case results. The environmental effects observed in cases 2 and 3 stem from toxicity and metal depletion, mainly linked to the PSC. Endpoint results revealed that when considering a PSC lifespan of 10 years or more, the detrimental ecosystem impacts of cases 2 and 3 become less severe than those of case 1. Uncertainty assessment has been done for different cases and impact categories. The study's results are also novel in which it evaluated the innovative PSC technology when integrated with other renewable resources, contrasting it with other integrated plants.

High‐Performance Inverted Perovskite Solar Cells by Dual Interfaces Modification with Identical Organic Salt

AbstractThe improvement of power conversion efficiency (PCE) and stability of perovskite solar cells (PSC) relies on the enhanced quality of perovskite layer and the modification of its adjacent interfaces. For this purpose, a multifunctional organic passivation molecule 1‐(4‐Fluorophenyl) biguanide hydrochloride (F‐BHCl) is introduced to the top and bottom interfaces of the perovskite layer. The PCE of PSC after the modification of double interfaces with F‐BHCl is significantly increased from 22.41% (unmodified) to 25.14%, and the storage, thermal, and operation stability is also improved. The comprehensive theoretical and experimental studies verify that due to its versatile functional groups and adaptation, F‐BHCl can significantly improve the quality of perovskite film, fully passivate several kinds of common defects, smoothen the top surfaces of perovskite film, and construct “molecular bridges” with carrier transporters on both the top and bottom surfaces, leading to significantly reduced non‐recombination and carrier transport losses. As a result, a significant increase is achieved in the open circuit voltage and fill factor as well as the whole performance of the device.

Buried interface modification toward efficient perovskite solar cell based on PVK hole transport layer

Poly (9-vinylcarbazole) (PVK) is an attractive hole transport material for organometallic-halide perovskite solar cell (PSC) because of its excellent hole transport ability and great film-forming property. Nowadays, the PVK hole-transport-layer (HTL) based PSC suffered from low power conversion efficiency (PCE), which mainly caused by bad interface contact between PVK and perovskite film, including the energy level mismatch. Doing PVK is an effective and facial method to modify the buried interface of perovskite film. In this work, 1,1-bis [(di-4-tolylamino)phenyl]cyclohexane (TAPC) was added into PVK HTL. Experimental results show that a highest occupied molecular orbital (HOMO) level elevation was achieved after doping TAPC. Meanwhile perovskite films with increased crystallinity, reduced defect density and enhanced light absorbance were obtained. Finally, the PCE of PSCs were enhanced from 10.81% of the control device to 15.65% of PVK + 40% TAPC device. The reason that responsible for the energy level lifting, morphology improvement and performance enhancement were thoroughly investigated and analyzed. This work provides an alternative option for the dopant in PVK to improve the buried interface of perovskite film, and therefore, the performance of PSCs.

High-Quality TiO2 Electron Transport Film Prepared via Vacuum Ultraviolet Illumination for MAPbI3 Perovskite Solar Cells.

The electron transport layer (ETL) plays an important role in determining the conversion efficiency and stability of perovskite solar cells (PSCs). Here, TiO2 thin film was prepared by irradiating diisopropoxy diacetylacetone titanium precursor thin film with 172 nm vacuum ultraviolet (VUV) at a low temperature. The prepared TiO2 thin film has higher electron mobility and conductivity. As it is used as an ETL for MAPbI3 PSCs, its band structure is better matched with the perovskite, and at the same time, due to the good interface contact, more uniform perovskite crystals are formed. Most importantly, a large number of hydroxyl radicals were formed during VUV irradiation of the precursor film, which made up for the oxygen defect present on the surface of the TiO2 thin film, and were adsorbed to the film surface. These hydroxyl groups form hydrogen bonds with methylammonium (MA) components on the MAPbI3 buried surface, thus promoting the transfer of photogenerated electrons at the MAPbI3/ETL interface. The power conversion efficiency of PSCs fabricated in air with the ETL prepared by VUV irradiation is 20.46%, which is higher than that of the contrast solar cell based on the sintered ETL (17.96%).

DFT Investigation of Structural Stability, Optical Properties, and PCE for All-Inorganic Csx(Pb/Sn)yXz Halide Perovskites.

Employing all-inorganic perovskites as light harvesters has recently drawn increasing attention owing to the strong-bonded inorganic components in the crystal. To achieve the systematic and comprehensive understanding for the structures and properties of Csx(Pb/Sn)yXz (X = F, Cl, Br, I) perovskites, this work provides the comparison details about crystal structures, optical properties, electronic structures and power conversion efficiency (PCE) of 18 perovskites. The suitable band gaps are detected in CsSnCl3-Pm3̅m (0.96 eV), γ-CsPbI3-Pnma (1.75 eV), and CsPbBr3-Pm3̅m (1.78 eV), facilitating the conversion from absorbing photon energy to generating hole-electron pairs. γ-CsPbI3-Pnma and CsSnI3-P4/mbm show superior visible-absorption performance depending on their higher absorption coefficient (α); meanwhile, strong peaks can be observed in the real part (Re) of photoconductivity of CsPbBr3-Pbnm, γ-CsPbI3-Pnma, and CsSnI3-P4/mbm in the visible-light range, implying their better photoelectric conversion abilities. The perovskite/tungsten disulfide (WS2) heterojunctions are constructed to calculate the PCE. Although just the PCE result (14.43%) of CsSnI3-Pnma/WS2 is reluctantly competitive, the predictions of PCEs indicate that the PCE of PSCs (perovskite solar cells) can be improved by not only regulating the perovskite to upgrade its own performance but also designing the PSC structure reasonably including the selection of appropriate ETL/HTL (electron/hole transport layer), etc.

Data‐Driven Approach to Accelerate the Design of Halide Perovskite for Photovoltaic Application Using Electronic Properties as Descriptors

Perovskite solar cells (PSCs) have garnered remarkable attention for their efficiency and tunable optoelectronic properties. However, their instability to moisture and heat poses challenges. Traditional trial‐and‐error approaches for finding stable halide perovskites are inefficient due to the vast compositional possibilities within ABX3 perovskite structure. This study uses machine learning (ML) to predict bandgaps and photovoltaic parameters of PSCs, using a dataset of 447 data points containing chemical composition, bandgaps, and photovoltaic parameters. Various ML models including support vector regressor, random forest, gradient boost regressor, XGBoost, extratree Regressor, and AdaBoost Regressor have been used herein. Positional average elemental property (PAEP) approach is introduced to featurize the data. As ABX3 perovskite involves distinct A, B, and X sites, the proposed PAEP model captures site‐specific effects, enhancing model accuracy. The best model exhibits impressive r‐values of 0.98 for bandgap prediction and 0.86 for power conversion efficiency of PSCs. Elemental properties of B and X sites, such as ionization energy, electron affinity, and electronegativity, are found to be crucial features in the analysis by Shapley additive explanation. This study underscores the potential of ML in designing novel, stable, and efficient PSCs, offering a more efficient alternative to conventional trial‐and‐error methods.

A regulation strategy of self-assembly molecules for achieving efficient inverted perovskite solar cells.

Self-assembled monolayers (SAMs) have been successfully employed to enhance the efficiency of inverted perovskite solar cells (PSCs) and perovskite/silicon tandem solar cells due to their facile low-temperature processing and superior device performance. Nevertheless, depositing uniform and dense SAMs with high surface coverage on metal oxide substrates remains a critical challenge. In this work, we propose a holistic strategy to construct composite hole transport layers (HTLs) by co-adsorbing mixed SAMs (MeO-2PACz and 2PACz) onto the surface of the H2O2-modified NiOx layer. The results demonstrate that the conductivity of the NiOx bulk phase is enhanced due to the H2O2 modification, thereby facilitating carrier transport. Furthermore, the hydroxyl-rich NiOx surface promotes uniform and dense adsorption of mixed SAM molecules while enhancing their anchoring stability. In addition, the energy level alignment at the interface is improved due to the utilization of mixed SAMs in an optimized ratio. Furthermore, the perovskite film crystal growth is facilitated by the uniform and dense composite HTLs. As a result, the power conversion efficiency of PSCs based on composite HTLs is boosted from 22.26% to 23.16%, along with enhanced operational stability. This work highlights the importance of designing and constructing NiOx/SAM composite HTLs as an effective strategy for enhancing both the performance and stability of inverted PSCs.

Triethylsilane introduced precursor engineering towards efficient and stable perovskite solar cells

Perovskite solar cells (PSCs) are believed to be optimistic for commercial deployment soon since the power conversion efficiency of PSCs presently reaches up to 26.10 % due to the intensive efforts these years. The two-step method is comparatively more suitable for scalable perovskite films, where lead halides and ammonium salts are prepared in separate precursors and deposited sequentially. Therefore, the reactivity between these two precursors governs the quality of final perovskite films and the intrinsic non-radiative recombination (NRR) at the perovskite's interfaces. Herein, we empowered both types of precursors, one by one and then simultaneously, with triethylsilane (TES) to investigate its effect on the (FAPbI3)1-x (MAPbBr3)x perovskite's morphological and optoelectronic properties. TES, with ethyl moieties and metalloid center, in ammonium salts delivers homogeneous perovskites' crystals and inhibits the NRR of perovskite films by reducing the defects and trap states. As a result, the optimized devices exhibit not only improved device performance (particularly for the increased fill factors and open circuit voltages) but also enhanced stabilities.

Controlling Lead Halide Residue in Perovskite Solar Cells: A Method to Improve the Photostability and Hysteresis

The presence of residual lead iodide phase in perovskite films, inherent to the two‐step spin‐coating method, has been reported to be beneficial for the performance of perovskite solar cells (PSCs); However, it may potentially undermine the photostability of PSCs. Herein, four distinct sets of perovskite films and devices are fabricated via the two‐step spin‐coating process, each under different processing conditions. All conditions demonstrate promising power conversion efficiency in PSCs. However, the aspect of photostability is found to be significantly influenced by unreacted PbI2 in the perovskite films. Varying degrees of residual PbI2 are detected among these films. Upon light exposure, it is observed that residual PbI2 within perovskites undergoes decomposition into metallic lead (Pb0) and mobile iodine, and these can affect the photovoltaic performance of the PSCs. The presence of mobile ions in metal–halide perovskites has generated substantial concern due to their impact on hysteresis within the J–V curve. Furthermore, the metallic lead (Pb0) containing perovskite films exhibits a prominent inverted hysteresis in the J–V curve

Preliminary exploration of the influence of N+/NHx+ ions/groups bombardment at TiO2 ETLs on performance of MAPbI3 perovskite solar cells

The service stability of organic–inorganic hybrid metal halide perovskite solar cells (PSCs) is one of most important factors, which is seriously influenced by the decomposition of perovskite layer. Especially, the decomposition of perovskite layer could deteriorate the interface between perovskite layer and TiO2 electron transport layer (ETL). In this work, TiO2 ETLs are prepared by the sputtering technique and traditional spin-coating technique. Then, TiO2 ETLs are bombarded by N+/NHx+ ions/groups. PSCs with all TiO2 ETLs are prepared and measured. The results show that after bombardment, N+/NHx+ ions/groups could chemically react with Ti/O ions at surface of TiO2 ETLs. As a result, the conduction band minimum and transfer resistance of TiO2 ETLs both deteriorate, which decrease the power conversion efficiency of PSCs seriously. While, because anatase TiO2 (001) crystal face consists of saturated O/Ti ions and displays the highest surface free energy, TiO2 ETLs with anatase (001) preferred orientation displays the optimal restraint on deterioration of power conversion efficiency caused by N+/NHx+ ions/groups bombardment. Based on above results, TiO2 ETLs with anatase (001) preferred orientation should be the optimal one for PSCs, which could improve the service stability obviously.

Two birds with one stone: dopant-free squaraine hole-transporting material for perovskite solar cell

Developing alternative dopant-free hole-transporting materials (HTM) with a passivation effect and high hole mobility is significant for enhancing the power conversion efficiency (PCE) and stability of the perovskite solar cells (PSCs) with a simplified process. In this work, we report a squaraine HTM 3,4-bis(4'-(bis(4-methoxyphenyl)amino)-[1,1′-biphenyl]-4-yl)cyclobut-3-ene-1,2-dione (D12) with a resonance central structure shuttling between electrically neutral dione and charge-separated inner salts. The donor-acceptor-donor type molecule D12 exhibits an extremely strong capacity not only for hole exaction and mobility, but also for the passivation of perovskite defects. This results in a high PCE of 22.32% for D12-based PSCs. After 30 days of aging at a high relative humidity of 65% at 30 °C, it remains 90% of its initial PCE. This work offers a strategy of designing dopant-free small-molecule HTM and enhancing the stability and PCE of PSCs.

The Role of Alpha‐Methylbenzyl Ammonium Iodide to Reduce Defect Densities in Perovskite Devices

Hybrid organic–inorganic perovskite photovoltaic has achieved unmatched power conversion efficiency (PCE) improvement in the last decade. Nevertheless, nonradiative recombination of charge carriers due to bulk and interface defects reduces the open‐circuit voltage (V oc) and PCE of perovskite solar cells. Incorporating additives, process optimization, and interface engineering are among the effective approaches employed to reduce such issues. Herein, quasi‐2D p–i–n perovskite solar cells incorporating alpha‐methylbenzyl ammonium iodide (MBAI) cation with outstanding photovoltaic performance and stability are developed. MBAI incorporation results in films with excellent optical and electrical properties, leading to higher V OC of ≈1.15 V, fill factor of above 77%, and stability of the device. A high open‐circuit voltage and fill factor and corrected power conversion efficiencies in the range of 15% are obtained for the prepared devices. The encapsulated solar cells show excellent operational stability under white light illumination in ambient air for >500 h. Due to the simple and robust preparation process, the investigated inverted perovskite solar cell can easily be combined with other solution‐processed thin film solar cells to form multijunction devices and can easily be integrated into different lightweight and flexible products.

Defect Regulation of Efficient Dion-Jacobson Quasi-2D Perovskite Solar Cells via a Polyaspartic Acid Interlayer.

Interfacial modification is a promising strategy to fabricate highly efficient perovskite solar cells (PSCs). Nevertheless, research studies about optimization for the performance of Dion-Jacobson (DJ)-phase quasi-2D PSCs by underlying surface modification are rarely reported. The relevant influence of interfacial modification on defect regulation in the bulk and at the interface for PSCs is still unexplored. Herein, an interlayer of polyaspartic acid (PASP) was introduced at the interface of a hole transporting layer and a perovskite absorber to regulate both the film quality and interface property for BDA-based DJ quasi-2D PSCs (n = 5). The PASP interlayer suppressed the charge recombination, restricted the interfacial charge accumulation, and promoted the charge transport in devices and therefore improved the power conversion efficiency of PSCs from 15.03 to 17.34%. Moreover, through device simulation, it was concluded that the increase of open-circuit voltage (Voc) was mainly attributed to the suppression of interface defects, while the increase of short-circuit current (Jsc) was ascribed to the restriction of interface defects and perovskite bulk defects. The improvement of both Voc and Jsc originated from the passivation of shallow defect states. The present work provides a promising route for the fabrication of efficient quasi-2D PSCs and enriches the fundamental understanding of defect regulation on photovoltaic performance.

A functionalized phosphorous tetrabenzotriazacorrole dye as a novel passivating agent of high-performance planar perovskite solar cells

Surface passivation is a crucial strategy to manage the film characteristics of solution-processed perovskite absorber layers, which greatly impact the photovoltaic properties of perovskite solar cells (PSCs). However, designing and synthesizing suitable passivating agents with required functional groups and solution-processability is challenging due to their complex molecular structure. In this study, we demonstrate a facile passivation technique using a functionalized phosphorous tetrabenzotriazacorrole dye (PTBC) for p-i-n PSCs. The tetrabenzotriazacorrole dye has amines and ether linkages that can closely interact with the undercoordinated Pb2+ with halogen vacancies through Lewis acid-base interactions, leading to a pinhole-free perovskite absorber layer with reduced trap density. Moreover, the central phosphorus of PTBC is functionalized with dimethoxy groups, which can provide a more hydrophobic surface in the perovskite absorber layer. Consequently, high-quality perovskite films (CsFAPbI3) prepared with PTBC exhibit improved optical, electrical, and morphological properties, as well as superior carrier transportation/recombination kinetics, boosting the power conversion efficiency of PSCs from 17.64 % to 20.08 %, with over 75 % of initial efficiency preserved after 1000 h of aging under ambient conditions. These results highlight PTBC as an effective surface passivation agent for perovskite absorber layers and emphasize the importance of suitable passivating agents in optimizing PSC performance.

Direct interface engineering using dopant of hole transport layer for efficient inorganic perovskite solar cells

With respect to the aim of achieving a suitable optical band gap and high thermal and chemical stability in next-generation perovskite solar cells (PSCs), inorganic CsPbI3 perovskite has gained significant attention. However, when it absorbs light, it quickly transforms into an undesired nonperovskite yellow phase at 25 °C. Therefore, it is crucial to stabilize the phase by reducing the defect density, which acts as a nonradiative recombination center at the interface of each layer. In this paper, we present an efficient interface treatment method that does not require any additional surface treatment such as annealing or coating, and the dopant Mn(TFSI)2 is directly mixed with the hole transporting material instead of bis(trifluoromethane)sulfonimide lithium salt (Li-TFSI). The use of Mn(TFSI)2 as a dopant diminishes the interfacial defects between the perovskite and hole transporting layer, reducing nonradiative recombination, increasing the lifetime of the carrier, and improving the power conversion efficiency from 16.5% for the control device using conventional Li-TFSI as a dopant to 17.6%. Moreover, the Mn(TFSI)2-doped device demonstrates superior long-term stability for 1000 h under ambient conditions without encapsulation, demonstrating 95% efficiency when compared with the initial performance. Therefore, Mn(TFSI)2 is a more powerful dopant of HTL and can increase the power conversion efficiency of PSCs by passivating the interface between the perovskite and HTL. Using Mn(TFSI)2, it is possible to quickly and effectively manufacture a stable inorganic perovskite device.

Enhancement in Power Conversion Efficiency of Perovskite Solar Cells by Reduced Non-Radiative Recombination Using a Brij C10-Mixed PEDOT:PSS Hole Transport Layer.

Interface properties between charge transport and perovskite light-absorbing layers have a significant impact on the power conversion efficiency (PCE) of perovskite solar cells (PSCs). Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) is a polyelectrolyte composite that is widely used as a hole transport layer (HTL) to facilitate hole transport from a perovskite layer to an anode. However, PEDOT:PSS must be modified using a functional additive because PSCs with a pristine PEDOT:PSS HTL do not exhibit a high PCE. Herein, we demonstrate an increase in the PCE of PSCs with a polyethylene glycol hexadecyl ether (Brij C10)-mixed PEDOT:PSS HTL. Photoelectron spectroscopy results show that the Brij C10 content becomes significantly high in the HTL surface composition with an increase in the Brij C10 concentration (0-5 wt%). The enhanced PSC performance, e.g., a PCE increase from 8.05 to 11.40%, is attributed to the reduction in non-radiative recombination at the interface between PEDOT:PSS and perovskite by the insulating Brij C10. These results indicate that the suppression of interface recombination is essential for attaining a high PCE for PSCs.

Lithium Fluoride Assisted Preparation of High‐Performance All‐Inorganic CsPbI3 Perovskite Solar Cells

All‐inorganic CsPbI3 perovskite is an ideal solar material with an appropriate bandgap (≈1.73 eV) that can be used for the top cell in tandem cells matched to crystalline silicon or low‐bandgap perovskites. Efficient all‐inorganic perovskite solar cells (PSCs) provide the cornerstone for efficient tandem cells. However, all‐inorganic PSCs are less efficient than organic–inorganic hybrids PSCs, and because CsPbI3 is incompatible with water, the stability of perovskite must be improved. Herein, a novel method for preparing efficient and stable PSCs via ionic chemical doping is proposed. Lithium fluoride as an inorganic ionic dopant can control grain growth and get larger grain sizes. The crystal structure, morphology, and electrochemical impedance spectroscopy of LiF‐doped all‐inorganic perovskite films are studied to determine the relationship between film quality and device performance. The doping of 2 mol% LiF considerably enhances the performance of the device, eliminates the hysteresis effect of the device, and the maximum power conversion efficiency of PSCs is raised to 17.02%. Additionally, device stability is greatly enhanced.