Device Performance Of Solar Cells Research Articles

Microscopic analysis of low but stable perovskite solar cell device performance using electron spin resonance

Perovskite solar cells have attracted much attention as next-generation solar cells. However, a typical hole-transport material, spiro-OMeTAD, has associated difficulties including tedious synthesis and high cost. To overcome these shortcomings, an easily synthesized and low-cost hole-transport material has been developed: HND-2NOMe. Although HND-2NOMe has high local charge mobility because of the quasi-planar structure, its lower device performance is a weak point, the cause of which has not yet been clarified. Here, we analyse the source of the lower performance by clarifying the internal states from a microscopic viewpoint using electron spin resonance. We observe hole diffusion from perovskite to HND-2NOMe under dark conditions, indicating hole barrier formation at the perovskite/HND-2NOMe interface, leading to lower performance. Although such a barrier is formed, less hole accumulation for the HND-2NOMe-based cells under solar irradiation occurs, which is related to the stable performance. The sources of the lower but stable performance are crucially important for providing guidelines for improving the device performance.

The effect of fluorinated conjugated side chains on the photovoltaic performance of polymers based on benzodithiophene (BDT) and carbazolobistriazole (CTA)

Reasonable regulation of the structure-performance relationship is extremely crucial to enhancing the device performance of organic solar cells (OSCs). As a novel fused-benzotriazole (BTA) electron-accepting (A) unit, carbazolobistriazole (CTA) has excellent luminescent properties, and the alkyl chains on the three N atoms allow flexible modulation of polymer solubility. However, higher molecular energy levels and weak crystallinity restrict the enhancement of device performance. Herein, a new donor polymer PE97 with CTA as A unit and 4,8-bis(4-(2-ethylhexyl)-3,5-difluorophenyl)benzo[1,2-b:4,5-b’]dithiophene (BDT-P2F) as electron-donating (D) unit was designed and synthesized. In comparison with the first CTA-based polymer PE93 with 4,8-bis(5-(2-ethylhexyl)-4-fluorothiophen-2-yl)benzo[1,2-b:4,5-b’]dithiophene (BDT-TF) as D unit, PE97 realizes stronger molecular stacking conducive to modulation of the active layer morphology and a deeper highest occupied molecular orbital (HOMO) level, which are favorable to increase short-circuit current density (JSC) and open-circuit voltage (VOC) of OSCs. When paired with Y-series non-fullerene acceptor eC9-2F, PE97-based OSC devices have achieved a higher power conversion efficiency (PCE) of 15.5 %, with a VOC of 0.81 V, a JSC of 25.3 mA cm−2, and a fill factor (FF) of 75.7 %, which figures significantly surpass efficiency (13.6 %) of PE93-based devices. These results indicate that the BDT-P2F unit can excellently modulate the optoelectronic properties of CTA-based polymers. This highlights the potential of the BDT-P2F as a promising D unit for polymers with weak crystallinity and limited electron-withdrawing properties.

The superiority of isomeric, fluorination and curtailed π-conjunction on A–D–A type acceptors for organic photovoltaics

The performance of organic solar cell (OSC) devices has been significantly enhanced by the dramatic evolution of A–D–A type non-fullerene acceptors (NFAs). Nevertheless, the structure–property-performance relationship of NFAs in the OSC device is unclear. Here, the intrinsic design factors of isomeric, fluorination and π-conjunction curtailing on the photophysical properties of benzodi (thienopyran) (BDTP) (named NBDTP-M, NBDTTP-M, NBDTP-Fin, and NBDTP-Fout)-based NFAs are discussed. The results show that fluorination on the terminal group of NBDTP-Fout could effectively decrease the highest occupied orbital (HOMO) energy level and the lowest unoccupied orbital (LUMO) energy level. And the long π-conjugated donor unit for NBDTTP-M could increase the HOMO energy level and bring a small HOMO-LUMO energy bandgap. Meanwhile, the substitution of external oxygen atoms and the fluorine atoms in the terminal group could introduce positive changes to the electrostatic potential of the NBDTP-Fout, favouring the charge separation at the donor/acceptor interface. Moreover, the structural design of external oxygen atom substitution, fluorination on the terminal group and curtailed π-conjugated donor unit could decrease the electron vibration-coupling of exciton diffusion, exciton dissociation and electronic transfer processes. The suppression of the exciton decay and charge recombination in those high-performance NFAs indicate that the investigated molecular designs could be effective for further improvement of OSCs.

Polyaniline/reduced graphene oxide nanocomposites for electrochemical and solar cell applications

Polyaniline nanocomposites are synthesized via in situ chemical oxidation method by reinforcing reduced graphene oxide nanoparticles of various weight percentage. Structural, optical, thermal and electrochemical studies are performed to know the significance of introducing reduced graphene oxide into polyaniline and to analyse the importance of filler weight percentage in determining various properties of the nanocomposites. X-ray diffraction peak intensity is appeared to be maximum for nanocomposite doped with 2% filler. This composite shows minimum crystallite size and maximum photoluminescence intensity. Maximum ID/IG ratio obtained for 2% filler added nanocomposite from Raman spectroscopy studies proved that the presence of more surface defects and recombination of charge carriers are the reasons for enhanced photoluminescence. Thermal stability is found to be better for a nanocomposite with 1% reduced graphene oxide and obtained a mass retention of 60% even after heating up-to 600 °C. SEM images give various shapes of nanocomposite such as nanorods, spherical nanoparticles and button shaped nanocomposites for different filler weight percentage. Carbon to oxygen ratio is observed to be decreased as the filler percentage increased from 1% to 4% in SEM-EDAX analysis. Polymer nanocomposite with 1% reinforcement possess maximum UV and visible absorption and is found to be decreased as filler concentration increased from 1 to 4%. Electrochemical analysis is performed for polyaniline and 1% reduced graphene oxide reinforced polyaniline nanocomposite. Specific capacitance of the electrode is obtained as 212 F g−1 and 609 F/g for polyaniline and nanocomposite respectively at a scan rate of 0.01 V/S. Solar cell device performance study shows that power conversion efficiency is 5.54% for 1% reduced graphene oxide nanocomposite, 4.7% for 2% reinforced, 4.16% for 3% filler and 3.61% for 4% nanocomposite.

(Invited) Role of the Energy Offset in the Charge Separation at the Donor: Acceptor Interface

The trade-off between the short-circuit current density and open-circuit voltage has been one of the largest bottlenecks for further improving the device performance of organic solar cells (OSCs). Therefore, understanding the limit to which the energy offset can be reduced and the physics underlying the trade-off relationship is crucial. This study provides a threshold energy that can ensure high charge photogeneration efficiencies for Y-series nonfullerene acceptor-based OSCs and discusses the role of the energy offset in charge separation. In this study, we used transient absorption spectroscopy to track the time evolution of electroabsorption caused by electron-hole pairs generated at donor:acceptor interfaces. We found that an insufficient energy offset led to not only slow charge transfer at the donor:acceptor interfaces, but also inefficient long-range spatial dissociation of the charge transfer states. Our findings highlight the importance of overcoming the trade-off between fill factor and open-circuit voltage for further improving the power conversion efficiency.

Boosted device performance of perovskite solar cells via KI processing additives

AbstractPerovskite solar cells (PSCs) have attracted great attention in both academic and industrial sectors in the past years. Studies demonstrated that processing additive engineering was a facile way to improve the crystallinity and minimize the defect of metal halide perovskites (MHPs). In this study, we report efficient and stable PSCs, where the MHPs thin film is processed with KI additives. It is found that the KI processing additives could not only enhance the crystallization and suppress the defects of MHP thin film, but also boost charge transport, suppress non-radiative recombination, and enhance the hydrophobic properties of MHP thin film. As a result, the PSCs based on the MHPs thin film processed with KI additives exhibit more than 10% enhancement in efficiency and dramatically boosted stability compared to that based on pristine MHPs thin film. Our results indicated that the MHPs processed with processing additives are a simple engineering technique to boost the device performance of PSCs.

Manipulating the Crystallization of Tin Halide Perovskites for Efficient Moisture-to-Electricity Conversion.

Manipulating the crystallization of perovskite in thin films is essential for the fabrication of any thin-film-based devices. Fabricating tin-based perovskite films from solution poses difficulties because tin tends to crystallize faster than the commonly used lead perovskite. To achieve optimal device performance in solar cells, the preferred method involves depositing tin perovskite under inert conditions using dimethyl sulfoxide (DMSO), which effectively retards the formation of the tin-bromine network, which is crucial for perovskite assembly. We found that under ambient conditions, a DMSO-based tin perovskite salt solution resulted in the formation of a two-phase system, SnBr4(DMSO)2 and MABr, whereas a dimethylformamide-based solution resulted in the formation of vacancy-ordered double perovskite MA2SnBr6. Humidity is known to solvate MABr to form the solvated ions, and so we used the two-phase system for the application in moisture to electricity conversion. The importance of the presence of the scaffold can be seen with the negligible power output from the vacancy-ordered double perovskite obtained with MA2SnBr6. We have fabricated a device with two-phase system that can generate an open-circuit potential of 520 mV and a short-circuit current density of 30.625 μA/cm2 at 85% RH. Also, the device charges a 10 μF capacitor from 150 mV at 51% RH to 500 mV at 85% RH in 6 s at a rate of 52.5 mV/s. Moreover, the output can be scaled by connecting devices in series and parallel configurations. A 527 nm green LED was powered by connecting five devices in series at 75% RH. This indicates a potential for utilizing these moisture-to-electricity conversion devices in powering low-energy requirement devices.

Surface Reconstruction for Efficient NiOx-Based Inverted Perovskite Solar Cells.

Functional agents are verified to efficiently enhance device performance of perovskite solar cells (PSCs) through surface engineering. However, the influence of intrinsic characteristics of molecules on final device performance is overlooked. Here, a surface reconstruction strategy is developed to enhance the efficiency of inverted PSCs by mitigating the adverse effects of lead chelation (LC) molecules. Bathocuproine (BCP) is chosen as the representative of LC molecules for its easy accessibility and outstanding optoelectronic properties. During this strategy, BCP molecules on perovskite surface are first dissolved in solvents and then captured specially by undercoordinated Pb2+ ions, preventing adverse n-type doping by the molecules themselves. In this case, the BCP molecule exhibits outstanding passivation effect on perovskite surface, which leads to an obviously increased open-circuit voltage (VOC). Therefore, a record power conversion efficiency of 25.64% for NiOx-based inverted PSCs is achieved, maintaining over 80% of initial efficiency after exposure to ambient condition for ≈1500 h.

5-Chlorobenzoxazole as solid additive for efficient organic solar cells

Adding solid additives to the active layer is a simple and efficient method to adjust the morphology of the active layer to obtain appropriate phase separation, thus improving the organic solar cell device performance. We found a 5-Chlorobenzoxazole molecule as a solid additive to PM6:Y6 system, which increased the filling factor from 66.2 % to 71.0 % and the PCE from 14.8 % to 16.1 %. The results indicate that 5-Chlorobenzoxazole can interact with Y6, thus optimizing the morphology of the active film, enhancing the ability of charge extraction, and further improving FF and PCE.

Eliminating Non-Corner-Sharing Octahedral for Efficient and Stable Perovskite Solar Cells.

The metal halide (BX6)4- octahedron, where B represents a metal cation and X represents a halide anion, is regarded as the fundamental structural and functional unit of metal halide perovskites. However, the influence of the way the (BX6)4- octahedra connect to each other has on the structural stability and optoelectronic properties of metal halide perovskite is still unclear. Here, the octahedral connectivity, including corner-, edge-, and face-sharing, of various CsxFA1-xPbI3 (0≤x≤0.3) perovskite films is tuned and reliably characterized through compositional and additive engineering, and with ultralow-dose transmission electron microscopy. It is found that the overall solar cell device performance, the charge carrier lifetime, the open-circuit voltage, and the current density-voltage hysteresis are all improved when the films consist of corner-sharing octahedra, and non-corner sharing phases are suppressed, even in films with the same chemical composition. Additionally, it is found that the structural, optoelectronic, and device performance stabilities are similarly enhanced when non-corner-sharing connectivities are suppressed. This approach, combining macroscopic device tests and microscopic material characterization, provides a powerful tool enabling a thorough understanding of the impact of octahedral connectivity on device performance, and opens a new parameter space for designing high-performance photovoltaic metal halide perovskite devices.

Preparation of wide bandgap CuGaSe2 absorbers and solar cells by sputtering a selenium-rich ceramic target and annealing in a selenium-free atmosphere

CuGaSe2 (CGSe) material possesses a wide bandgap of approximately 1.7 eV, making it a promising prospect for top cells in tandem solar cells. Depositing CGSe precursor films by magnetron sputtering of a selenium-rich ceramic target is easy to operate and control. After annealing the precursor films at different temperatures in a selenium-free argon atmosphere, avoiding the use of toxic H2Se. To achieve an absorber exhibiting appropriate performance, the morphologies, phase composition, absorption characteristics, roughness, lattice structure, and work function of CGSe absorbers annealed at different temperatures were investigated. The CGSe absorber annealed at 550 °C showed uniform grain, a single-phase composition, high absorbance, flat surface, and compact crystal structure. The absorber annealed at excessive temperature led to the formation of Cu2-xSe, inducing defects and carrier recombination. The work function of CGSe absorber annealed at 590 °C increases, resulting in the misalignment of its band with the Mo back contact. The enhancement of absorber contributes positively to solar cell device performance. CGSe solar cells prepared using the absorber annealed at 550 °C exhibited excellent photoelectric properties. The increase in minority carrier lifetime and recombination resistance improves the transport characteristics of carriers.

Perovskite solar cells with ferroelectricity

AbstractHalide perovskites show excellent optoelectronic properties for solar cell application. Notably, perovskite crystalline structures have been widely reported to deliver superior ferroelectric properties. As a result, the integration of the ferroelectric process with the photon‐to‐electron energy conversion process becomes feasible to generate interesting photo‐physical properties and further boost the device performance of perovskite solar cells (PSCs), which have started to attract more and more attention in recent years. Here, we have reviewed the recent progress in PSCs with ferroelectricity (FE‐PSCs), by classifying them into three regimes according to the degree of phase segregation, for example, the layer‐structured ferroelectric/halide perovskite composite, micro phase‐separated ferroelectric/halide perovskite composite, and the intrinsic ferroelectric halide perovskite composite. The different composite structures enable a large range of interesting optoelectronic properties and the specific structure significantly enhances the device performance of PSCs. The most prominent contribution of ferroelectricity is that it can provide an extra electrical field to drive charge generation, transport, and collection. Further, key challenges and opportunities of the integration of ferroelectricity with photovoltaics are discussed. We hope our work can draw intensive attention in this field to accelerate the establishment of the basic theories in ferroelectricity and the commercialization of PSCs.

Three Effective Methods for Passivation of Perovskite Solar Cell Defects

Perovskite solar cells have garnered significant attention due to their outstanding photoelectric properties. However, the majority of widely used perovskite polycrystalline ion crystal films are prepared through solution treatment processes, which often lead to the formation of high-density defects during the crystallization process. These defects within the device can be quite severe and are a major contributor to non-radiative recombination, limiting the enhancement of photovoltaic performance and stability of solar cell devices. In this paper, we review the latest advancements in defect passivation strategies for perovskite crystals, encompassing Lewis acid, Lewis base, and Lewis acid-base synergy approaches. We delve into the regulatory mechanisms and passivation effects of these various strategies on perovskite surface/interface defects. Furthermore, we anticipate the application of these defect passivation techniques in future studies, hoping to further enhance the performance and stability of perovskite solar cells.

Effect of Position of Donor Units and Alkyl Groups on Dye-Sensitized Solar Cell Device Performance: Indoline-Aniline Donor-Based Visible Light Active Unsymmetrical Squaraine Dyes.

Indoline (In) and aniline (An) donor-based visible light active unsymmetrical squaraine (SQ) dyes were synthesized for dye-sensitized solar cells (DSSCs), where the position of An and In units was changed with respect to the anchoring group (carboxylic acid) to have In-SQ-An-CO2H and An-SQ-In-CO2H sensitizers, AS1-AS5. Linear or branched alkyl groups were functionalized with the N atom of either In or An units to control the aggregation of the dyes on TiO2. AS1-AS5 exhibit an isomeric π-framework where the squaric acid unit is placed in the middle, where AS2 and AS5 dyes possess the anchoring group connected with the An donor, and AS1, AS3, and AS4 dyes having the anchoring group connected with the In donor. Hence, the conjugation between the middle squaric acid acceptor unit and the anchoring -CO2H group is short for AS2, AS5, and AK2 and longer for AS1, AS3, and AS4 dyes. AS dyes showed absorption between 501 and 535 nm with extinction coefficients of 1.46-1.61 × 105 M-1 cm-1. Further, the isomeric π-framework of An-SQ-In-CO2H and In-SQ-An-CO2H exhibited by means of changing the position of In and An units a bathochromic shift in the absorption properties of AS2 and AS5 compared to the AS1, AS3, and AS4 dyes. The DSSC device fabricated with the dyes contains short acceptor-anchoring group distance (AS2 and AS5) showed high photovoltaic performances compared to the dyes having longer distance (AS1, AS3, and AS4) with the iodolyte (I-/I3-) electrolyte. DSSC device efficiencies of 5.49, 6.34, 6.16, and 5.57% have been achieved for AS1, AS2, AS3, and AS4 dyes, respectively; without chenodeoxycholic acid (CDCA), small changes have been observed in the device performance of the AS dyes with CDCA. Significant changes have been noted in the DSSC parameters (open-circuit voltage VOC, short-circuit current JSC, fill factor ff, and efficiency η) for the AS5 dye while sensitized with CDCA and showed highest DSSC efficiency of 8.01% in the AS dye series. This study revealed the potential of shorter SQ acceptor-anchoring group distance over the longer one and the importance of alkyl groups on the overall DSSC device performance for the unsymmetrical squaraine dyes.

Regulating SnZn defects and optimizing bandgap in the Cu2ZnSn(S,Se)4 absorption layer by Ge gradient doping for efficient kesterite solar cells

In recent years, the primary reasons for low efficiency Cu2ZnSn(S,Se)4 (CZTSSe) solar cells have been attributed to SnZn defects and related defect clusters, as well as the balance of absorption layer bandgap for short-circuit current density (Jsc) and open-circuit voltage (Voc). Ge gradient has been theoretically proven to be an effective strategy to change traditional flat bandgap structure and suppress SnZn defects and related defect clusters for improving the device performance of CZTSSe solar cells. However, the potential of Ge gradient has not been fully verified. In this work, Ge doping effectively reduces the formation of SnZn defects and [2CuZn + SnZn] defect clusters in the CZTSSe absorption layer. In addition, it can be found that the construction of the V-type bandgap is the best solution for balancing between Voc and Jsc. By using the bandgap grading strategy, the disparity between the recombination barrier of the junction and the optical bandgap's minimum value is widened, thereby obtaining a large Voc. The V-type doped device has the highest efficiency when Voc is 0.45 V, which can reach 8.03%. This Ge graded substitution method provides an alternative absorption layer structure for improving Voc and the preparation of future high-efficiency kesterite photovoltaic devices.

Optimal modeling of perovskite solar cell with graphene oxide as hole transport layer using L32 (28) Taguchi design

Material parameter variations are one of the main contributors affecting the performance of solar cell devices, thus, Taguchi design is employed to optimize the material parameters in attaining maximum power conversion efficiency (PCE). This paper discusses the optimal modeling of the Perovskite solar cell (PSC) with graphene oxide (GO) hole transport layer (HTL) using L32 (28) Taguchi design. The device simulation is conducted using a solar cell capacitance simulator (SCAP), whereas the L32 (28) Taguchi design is used for device optimization. The final results reveal that the L32 (28) Taguchi design has significantly optimized the device parameters in which FTO thickness, FTO donor concentration, TiO2 thickness, TiO2 donor concentration, CH3NH3PbI3-xClx thickness, CH3NH3PbI3-xClx donor concentration, GO thickness and GO acceptor concentration are predictively set to 0.1 µm, 1 x 1020 cm-3, 0.03 µm, 1 x 1020 cm-3, 0.9 µm, 1 x 1020 cm-3, 0.03 µm and 1 x 1020 cm-3 correspondingly. Analysis of variance (ANOVA) reveals that the CH3NH3PbI3-XClX thickness is the most dominant input parameter affecting the PCE of the device. The optimized input parameters yield the maximum attainable PCE of 35.91% with a signal-to-noise ratio (SNR) of 31.11 dB.

The charm of entwining two major competitors CZTS & CH3NH3SnI3 to feasibly explore photovoltaic world beyond Shockley–Queisser limit

Many studies have reported CH3NH3SnI3-based solar cell having CZTS as hole transporter. In this paper, we have presented for the first time, an intensive analysis on CZTS-based solar cell device performance which has CH3NH3SnI3 as hole transporter. The proposed solar cell configuration is CH3NH3SnI3/CZTS/CdS/ZnO/AZO. The device optimization is performed in terms of layer thickness, carrier concentration, defect density, electron affinity, series resistance and shunt resistance. During optimization process, analysis of evolution in band structure, electric field, recombination rate and generation rate is utilized to provide proper explanation of device behavior. Finally, device is shown to perform very efficiently and reach highest efficiency value of 37.12 %. This sets up a new record in the history of theoretical development of CZTS-based solar cells. Moreover, it can be noted that the proposed experimentally-achievable solar cell has the potential to exceed the Shockley–Queisser limit for single-junction CZTS solar cells (32.1 %). The choice of CH3NH3SnI3 as an HTL in CZTS-based solar cell significantly enhances the electric field generation and substantially suppresses the recombination rate. Furthermore, the grace of series resistance optimization is discovered to lead to a very highly efficient device that performs beyond Shockley–Queisser limit.

Unveiling the Role of Ge in CZTSSe Solar Cells by Advanced Micro-To-Atom Scale Characterizations.

Kesterite is an earth-abundant energy material with high predicted power conversion efficiency, making it a sustainable and promising option for photovoltaics. However, a large open circuit voltage Voc deficit due to non-radiative recombination at intrinsic defects remains a major hurdle, limiting device performance. Incorporating Ge into the kesterite structure emerges as an effective approach for enhancing performance by manipulating defects and morphology. Herein, how different amounts of Ge affect the kesterite growth pathways through the combination of advanced microscopy characterization techniques are systematically investigated. The results demonstrate the significance of incorporating Ge during the selenization process of the CZTSSe thin film. At high temperature, the Ge incorporation effectively delays the selenization process due to the formation of a ZnSe layer on top of the metal alloys through decomposition of the Cu-Zn alloy and formation of Cu-Sn alloy, subsequently forming of Cu-Sn-Se phase. Such an effect is compounded by more Ge incorporation that further postpones kesterite formation. Furthermore, introducing Ge mitigates detrimental "horizontal" grain boundaries by increasing the grain size on upper layer. The Ge incorporation strategy discussed in this study holds great promise for improving device performance and grain quality in CZTSSe and other polycrystalline chalcogenide solar cells.

Role of Al doping in morphology and interface of Al-doped ZnO/CuO film for device performance of thin film-based heterojunction solar cells

Al-doped ZnO (AZO) at different doping concentrations are synthesized by the chemical bath deposition process. The X-ray diffraction results are confirmed the formation of hexagonal structure of ZnO. The doping concentration of Al in ZnO is varied the shape and size of AZO structures. These AZO structures are used for the fabrication of the heterojunction (ZnO/CuO) solar cell. The photoluminescence results are shown a smaller number of defects in AZO thin films. The potential barrier and ideality factor are obtained at 0.855 eV and 2.89 for 3 mol% doping of Al-doped thin-film solar cell diode. The interface of ZnO/CuO is analyzed by impedance spectra and Capacitance-frequency results. The maximum efficiency for device is recorded with a high fill factor at 3 mol% Al doped ZnO thin film based solar cell. This increased in the power conversion efficiency of device is originated from enhanced the optical properties, outstanding charge extraction efficiency, and suppressed the recombination of charge on the interface of CuO and AZO (3 mol%) layers, as revealed by the measurement of electrical, optical, and impedance spectroscopy.

Promoting Ruddlesden-Popper Perovskite Formation by Tailoring Spacer Intramolecular Interaction for Efficient and Stable Solar Cells.

Low-dimensional Ruddlesden-Popper phase (LDRP) perovskites are widely studied in the field of photovoltaics due to their tunable energy-band properties, enhanced photostability, and improved environmental stability compared to the 3D perovskites. However, the insulating spacers with weak intramolecular interaction used in LDRP materials limit the out-of-plane charge transport, leading to poor device performance of LDRP perovskite solar cells (PSCs). Here, a functional ligand, 3-guanidinopropanoic acid (GPA), which is capable of forming strong intramolecular hydrogen bonds through the carboxylic acid group, is employed as an organic spacer for LDRP PSCs. Owing to the strong interaction between GPA molecules, high-quality LDRP (GPA)2(MA)n-1PbnI3n+1 film with promoted formation of n = 5 phase, improved crystallinity, preferential vertical growth orientations, reduced trap-state density, and prolonged carrier lifetime is achieved using GPAI as the dimensionality regulator compared to butylamine hydroiodide (BAI). As a result, GPA-based LDRP PSC exhibits a champion power conversion efficiency of 18.16% that is much superior to the BA-based LDRP PSC (15.43%). Importantly, the optimized GPA-based LDRP PSCs without encapsulation show enhanced illumination, thermal, storage, and humidity stability compared to BA-based ones. This work provides new insights into producing high n value LDRP films and their efficient and stable PSCs.