Component Of Perovskite Solar Cells Research Articles

Optimization of an inorganic lead free RbGeI3 based perovskite solar cell by SCAPS-1D simulation

The toxic lead component of perovskite solar cells poses a hindrance to their commercialization. The state-of-art organic HTM, Spiro-OMeTAD has a high synthetic cost because of its complex synthesis procedure. In the present work, an all inorganic, lead free n-i-p planar RbGeI3-based PSC was demonstrated through SCAPS-1D simulation. The effect of various HTL and ETL materials, their thickness, thickness of perovskite layer, ETL doping concentration, HTL doping concentration, doping concentration of the absorber, defect density of perovskite layer, defect density of ETL/absorber and absorber/HTL interface, various back contacts, series resistance, shunt resistance and temperature on the performance of perovskite solar cell (PSC) has been analysed. The optimized device exhibited a power conversion efficiency (PCE) of 10.11%, fill factor (FF) of 63.68% and quantum efficiency (QE) of 90.3% in the visible range. This study demonstrates the potential of RbGeI3 as a perovskite material to achieve toxicity free renewable energy.

Remarkable performance optimization of inverted p-i-n architecture perovskite solar cell with CZTS as hole transport material

Hole transport material (HTM) is a major component of perovskite solar cells (PSCs). PEDOT: PSS, an organic HTM, is widely used in inverted (p-i-n) PSCs. While PEDOT: PSS is unstable, expensive and it's acidic nature could deteriorate the absorber. Copper zinc tin sulphide (CZTS), an inorganic semiconductor can be used as HTM due to its properties such as low cost, ease of synthesis and high hole mobility. In this work, device simulation of inverted (p-i-n) PSC was performed with CZTS as HTM to exploit its maximum capability. Remarkable power conversion efficiency (PCE) of 25.43% was achieved after optimizing the performance. Device performance was strongly affected by thickness and electron affinity of HTM as well as diffusion length of carriers. PCE of real fabricated device was also found to be 9.72%. This work demonstrates CZTS is a promising candidate to replace PEDOT: PSS from both experimental and theoretical perspectives.

Cyclopentadiene‐Based Hole‐Transport Material for Cost‐Reduced Stabilized Perovskite Solar Cells with Power Conversion Efficiencies Over 23%

AbstractHole transport materials (HTM) are an important component in perovskite solar cells (PSC). Despite a multitude of HTMs developed in recent years, only few of them lead to solar cells with efficiencies over 20%. Therefore, it is still a challenge to develop high‐performing HTMs, which have ideal energy levels of the frontier orbitals, are highly efficient in transporting charges, and stabilize the solar cell at the same time. In this work, the development of a structurally novel molecular HTM, CPDA 1, is described which is based on a common cyclopentadiene core and can be efficiently and inexpensively synthesized from readily available starting materials, which is important for future realization of low‐cost photovoltaics on larger scale. Due to excellent optoelectronic, thermal, and transport properties, CPDA 1 not only meets the envisioned properties by reaching high efficiencies of 23.1%, which is among the highest reported to date, but also contributes to a respectable long‐term stability of the PSCs.

Constructing CdS-Based Electron Transporting Layers With Efficient Electron Extraction for Perovskite Solar Cells

The electron transporting layer (ETL) is a critical component in perovskite solar cells (PSCs) and plays an important role in extracting and transporting electrons. However, the commonly used wide-bandgap metal oxides (TiO2, ZnO, SnO2, etc.) often involve undesirable photocatalytic activity towards perovskite materials under UV light, which would undermine the long-term stability of PSCs. In this article, nonoxide CdS ultra-thin films were deposited onto conducting substrates through chemical bath deposition to serve as ETLs. It is revealed that the subsequent CdCl2 treatment followed by annealing is not essential to CdS ETLs for PSCs; this fact is quite different from the scenario demonstrated for conventional thin-film solar cells. Moreover, a compact TiO2 (c-TiO2) blocking layer was introduced between the conducting substrate and the CdS layer to further enhance the electron extraction capability of ETLs and boost the photovoltaic performance of PSCs. Through careful morphology, optical and electrical characterizations, it is found that the presence of the c-TiO2 underlayer avoids the partially exposure of substrate bumps, enlarges the subsequently deposited perovskite crystals, forms cascade energy level alignments, and accelerates the electron extraction from perovskite to ETLs. Therefore, the shunt current leakage and the charge recombination at the ETL/perovskite interface are significantly suppressed. Eventually, the CH3NH3PbI3 PSC based on the bilayer c-TiO2/CdS ETL yields a promising power conversion efficiency of 15.11%, which is much higher than that of the single-layer CdS-based device. This work delivers one of the few CdS ETL-based PSCs that exhibit efficiencies over 15%.

Hole‐Transporting Molecules with Tetrabenzo[a,c,g,i]carbazole Core for Highly Efficient Perovskite Solar Cells

Hole‐transporting materials (HTMs) are the key component of perovskite solar cells (PSCs) for the role of extracting photogenerated holes, as well as the charge transporting between perovskite layer and metal electrode. Herein, with the aim to enhance the hole mobility by compact molecular packing, the modification of HTMs focuses on the extension of conjugated cores from the commonly used carbazole (Cz) to tetrabenzo[a,c,g,i]carbazole (TBC). Because of the closely cofacial stacking mode of the TBC core with an X‐type symmetric structure, the resultant TBC‐2,7,11,16‐tetra‐diphenylamine (TD) can achieve a hole mobility of 6.6 × 10−4 cm2 V−1 s−1 and the corresponding conversion efficiency of 20.52%, higher than that of the analogue Cz‐TD (18.34%).

Electron Beam Irradiation of Lead Halide Perovskite Solar Cells: Dedoping of Organic Hole Transport Materials despite Hardness of the Perovskite Layer.

Organic-inorganic lead halide perovskite solar cells (PSCs) are highly efficient, flexible, lightweight, and even tolerant to radiation, such as protons, electron beams (EB), and γ-rays, all of which makes them plausible candidates for use in space satellites and spacecrafts. However, the mechanisms of radiation damage of each component of PSC [an organic hole transport material (HTM), a perovskite layer, and an electron transport material (ETM)] are not yet fully understood. Herein, we investigated the EB irradiation effect (100 keV, up to 2.5 × 1015 cm-2) on binary-mixed A site cations and halide perovskite (MA0.13FA0.87PbI2.61Br0.39, MA:methylammonium cation and FA:formaminidium cation), a molecular HTM of doped SpiroOMeTAD, and an inorganic ETM of mesoporous TiO2. Despite the decreased power conversion efficiency of PSCs upon EB exposure, the photoconductivities of the perovskite, HTM, and ETM layers remained intact. In contrast, significant dedoping of HTM was observed, as confirmed by steady-state conductivity, photoabsorption, and X-ray photoelectron spectroscopy measurements. Notably, this damage could be healed by exposure to short-wavelength light, leading to a partial recovery of the PSC efficiency. Our work exemplifies the robustness of perovskite against EB and the degradation mechanism of the overall PSC performance.

Effect of isomeric hole-transporting materials on perovskite solar cell performance

As an important component of perovskite solar cells (PSCs), hole transport materials (HTMs) are of great significance to improve the efficiency and long-term stability of PSCs. When designing HTMs, hole mobility is an important concern; meanwhile, the ability to passivate defects in perovskite has to be taken into consideration. Herein, we introduced dipyridyl ketone as the core moiety to construct two isomers XJ2 and XJ3. The two isomers are distinguished by the position of the carbonyl group with respect to the N atom on the pyridine ring. Studies show that different positions of the CO group result in different electronic properties of the two isomers. The meta substitution of the carbonyl group in XJ2 endows it with a lower energy level and higher hole mobility compared with its counterpart XJ3. Such rational design also endows the defect passivation ability, and XJ2 exhibits a stronger passivation effect due to the smaller steric hindrance effect. As a result, the power conversion efficiency (PCE) of the XJ2-based device reaches 20.17%, which is much higher than the device with XJ3 as the HTM (18.84%).

Performance of perovskite solar cell coated with graphene oxide as hole transport layer

Organic metal halide perovskite has recently shown great potential for applications, as it has the advantages of low cost, excellent photoelectric properties, and high power conversion efficiency. The Hole Transport Material (HTM) is one of the most critical components in Perovskite Solar Cells (PSC). It has the function of optimizing the interface, adjusting the energy compatibility, and obtaining higher PCE. The inorganic p-type semiconductor is an alternative HTM due to its chemical stability, higher mobility, increased transparency in the visible region, and general valence band energy level (VB). Here we report the use of the Graphene Oxide (GO) layer as a Hole Transport Layer (HTL) to improve the perovskite solar cells' performance. The crystal structure and thickness of GO significantly affect the increase in solar cell efficiency. This perovskite film must show a high degree of crystallinity. The configuration of the perovskite material is FTO/NiO/GO/CH3NH3PbI3/ZnO/Ag. GO as a Hole Transport Layer can increase positively charged electrons' mobility to improve current and voltage. As a blocking layer that can prevent recombination. The GO can make the perovskite interface layer with smoother holes, and molecular uniformity occurs to reduce recombination. The method used in this study is by using spin coating. In the spin-coating process, the GO layer is coated on top of NiO with variations in the rotation of 700 rpm, 800 rpm, 900 rpm, 1,000 rpm, and 1,500 rpm. The procedure formed different thicknesses from 332.5 nm, 314.7 nm, 256.4 nm, 227.4 to 204.5 nm. The results obtained at a thickness of 227.4 nm reached the optimum efficiency, namely 15,3 %. Thus, the GO material as a Hole Transport Layer can support solar cell performance improvement by not being too thick and thin

Recent progress of doping strategies for organic hole transport materials in perovskite solar cells

<p indent=0mm>Organic-inorganic hybrid<bold> </bold>perovskite materials demonstrate outstanding optoelectronic properties, including high light absorption capacity, ambipolar charge transport, high defects tolerance. The application of perovskite materials in solar cells shows impressive progress by increasing the power conversion efficiencies (PCEs) from 3.8% to over 25%. Moreover, perovskite solar cells (PSCs) have the advantages of low materials cost and simple fabrication, giving rise to high potentials for future applications. The fast improvement in the photovoltaic performance of PSCs is mainly attributed to the intensive optimization in perovskite composition, device architecture, defects passivation, contact materials and perovskite crystallization kinetics. Contact materials, especially hole transport materials (HTMs), are key components in PSCs, which can not only affect the PCEs of PSCs, but also greatly influence the stability of devices. 2,2′,7,7′-Tetrakis[<italic>N</italic>,<italic>N</italic>-di(4-methoxyphenyl)amino]-9,9′-spirobifluorene (spiro-OMeTAD) is one of the most popularly used HTMs in PSCs and widely seen as a standard HTM for comparison. However, the synthetic process of spiro-OMeTAD is tedious and complex, leading to a high material cost. Moreover, spiro-OMeTAD has relatively low mobility, and chemical doping is one of the most efficient ways to improve the hole conductivity. So far different types of inorganic and organic dopants have been reported and their effects on photovoltaic performance are investigated. On the one hand, the introduction of chemical dopants can induce extra positive charges in HTMs and therefore enhance the conductivity. In this respect, doping efficiency is one critical factor for developing new dopants. On the other hand, research shows that chemical dopants can induce side effects in stability of HTMs and interfaces, limiting the lifetime of the PSCs devices. In this review, we first discuss the categories of HTMs and their specific advantages. Compared with inorganic HTMs, organic HTMs attract great attention because of high structural tunability, low cost and solution processability. However, organic molecules generally have low mobility, limiting their charge transport capacity. Therefore, doping by inducing redox reaction is the most effective way to enhance the conductivity of organic materials. Also, the doping mechanism slightly varies with different dopants and doping procedures are different. We focus on the progress of different chemical dopants in PSCs, and their roles and doping efficiencies in HTMs are briefly compared. We use spiro-OMeTAD as a reference HTM and conclude the influences of dopants on the conductivity and photovoltaic parameters in PSCs. The dopants include metal-based salts, ionic liquid and other molecules. Therein, dopants based on lithium bis-trifluoromethanesulfonimide (LiTFSI) and 4-tert-butylpyridine (TBP) are widely used in organic HTMs, but recent work shows that these additives have deleterious effects on device stability. Specifically, it is found LiTFSI migrates and accumulates at interfaces under the conditions of bias potentials. TBP has a relatively low boiling point and can easily evaporate at high temperatures, and also causes corrosion at perovskite interfaces. Therefore, developing alternative dopants and investigating their stability are crucial for future scalable applications in PSCs. Finally, we discuss the potentials of dopants in terms of future applications, and believe that developing new dopants with high stability is highly desired. Alternatively, designing efficient dopant-free HTMs is another strategy for obtaining stable HTMs for PSCs.

Fused Dithienopicenocarbazole Enabling High Mobility Dopant-Free Hole-Transporting Polymers for Efficient and Stable Perovskite Solar Cells.

As a critical component in perovskite solar cells (PSCs), hole-transporting materials (HTMs) have been extensively explored. To develop efficient dopant-free HTMs for PSCs, a decent hole mobility (>10-3 cm2 V-1 s-1) is critically essential, which is, however, seldom reported. In this work, we introduce two novel donor-acceptor (D-A) type conjugated polymers (PDTPC-1 and PDTPC-2) with narrow bandgap unit, i.e., fused dithienopicenocarbazole (DTPC), as the donor building block and benzo[c][1,2,5]thiadiazole derivatives as the acceptors. The highly planar and strong electron-donating DTPC endows the polymers with superior hole mobility up to ∼4 × 10-3 cm2 V-1 s-1. Because of the better energy alignment with perovskite and excellent film-forming property, PSCs with PDTPC-1 as HTM show an appreciably enhanced PCE of ∼17% in dopant-free PSCs along with improved device stability as opposed to PDTPC-2. Our work revealed for the first time that the introduction of narrow bandgap DTPC in D-A polymers could achieve remarkably high hole mobility in the pristine form, favoring the application in dopant-free PSCs.

Research progress of inverted planar perovskite solar cells based on nickel oxide as hole transport layer

In recent years, organic-inorganic hybrid perovskite solar cells (PSCs) have attracted wide attention due to their high photoelectric conversion efficiency and simple preparation process. Hole transport layer (HTL) is one of the most critical components in PSCs. As a kind of inorganic HTL material, nickel oxide (NiO&lt;sub&gt;&lt;i&gt;x&lt;/i&gt;&lt;/sub&gt;) has been widely used in perovskite solar cells because of its excellent advantages, such as outstanding chemical stability, high carrier mobility, simple methods for its preparation, etc. In this paper, the applications of NiO&lt;sub&gt;&lt;i&gt;x&lt;/i&gt;&lt;/sub&gt; HTL in planar PSCs are systematically summarized from the aspects of the improvment of its structure and photoelectric properties by doping and interface modification. The reasons for affecting the device performances, &lt;i&gt;i.e&lt;/i&gt;. fill factor, open-circuit voltage, short-circuit current, photoelectric conversion efficiency, and stability are emphatically analyzed from several aspects, such as energy level matching, hole mobility and crystallinity. In addition, the future development directions of the planar PSCs are prospected.

Recent Advances in Carbon Nanotube Utilizations in Perovskite Solar Cells

AbstractMetal halide perovskite solar cells (PSCs) have emerged as promising next‐generation photovoltaic devices with the maximum output efficiency exceeding 25%. Despite significant advances, there are many challenges to achieve high efficiency, stability, and low‐cost simultaneously. Combating these challenges depends on developing novel materials and modifying conventional device components. Carbon nanotubes (CNTs) have attracted considerable attention for fabricating efficient PSCs owing to their remarkable electrical, optical, and mechanical properties. With their multifunctional features, CNTs can play a wide range of roles and offer unique benefits in various components in PSCs to improve device performance and durability. Here, recent progress concerning the utilizations of CNTs as transparent conductive electrodes, charge‐transporter, perovskite additives, interlayers, hole‐transporting materials, and back electrodes in PSCs is comprehensively reviewed. The application of CNTs toward the development of 1D and 2D flexible PSCs is also discussed. A summary of current challenges and prospective on future research directions of employing CNTs to realize high‐performance PSCs is presented.

Leaching potential of chemical species from real perovskite and silicon solar cells

Despite their many advantages, solar photovoltaic (PV) cells used for electricity generation can have negative environmental impacts. The chemicals necessary for their fabrication can be released into the environment during their disposal or following damage, such as that from natural disasters. The principle objective of this study was to assess the leaching potential of chemical species, primarily heavy metals, from perovskite solar cells (PSC), monocrystalline (MoSC) silicon solar cells, and polycrystalline (PoSC) silicon solar cells under worst-case natural scenarios. In all cases, real solar cells were used as opposed to the pure component. The toxicity characteristic leaching procedure (TCLP) was used to analyze the leachates from PSCs to determine the concentrations of major component species. The results showed that broken PSCs released Si, Pb, Al, As, and Ni under TCLP conditions; lead, a major component of PSCs, was released at around 1.0 mg/L at a pH of 4.93, from both broken and unbroken PSCs. However, the concentrations of these elements in the leachate were within the toxicity characteristic (TC) limits. Encapsulation of the PSCs inhibited the release of hazardous substances, but did not completely eliminate the release of metals. TCLP results from broken MoSCs revealed that metals leached at relatively high levels: Al: 182 mg/L, Ni: 7.7 mg/L, and Cu: 3.6 mg/L. The results from broken PoSCs indicated the release of 43.9 mg/L of Cu and 6.6 mg/L of Pb, which are higher than the TC limits. These high levels may be attributed to the welding materials used on the rear side of crystalline-Si (c-Si) solar cells. This study identifies the importance of encapsulating PSCs and the welding materials on the rear side of c-Si solar cells to minimize the release of toxic substances into the environment.

Investigation of p-type SnO films served as a potential hole-transporting material for highly efficient perovskite solar cells

As an essential component of perovskite solar cells (PSCs), the design of hole transport materials (HTMs) has always been a topic of interest in the photovoltaic community. In this work, p-type tin monoxide (SnO) films are grown by electron beam evaporation to investigate the influence of substrate temperature and deposition time on their properties. The film crystallization and preferred growth orientation of (001) showed prominent enhancement with the increase in substrate temperature. The prolongation of deposition time witnessed changes in grain morphology from nanoparticles to nanosheets. Hall measurements revealed that the film deposited at 200 °C showed the lowest resistivity, the maximum carrier concentration, and the lowest carrier mobility. Using these films as HTMs, the performance of PSCs based on caesium lead iodide perovskites (CsPbI3) was analyzed theoretically and experimentally, and high open-circuit voltage (VOC) of 1.16 V is obtained. With the increase of the substrate temperature, the power conversion efficiency of PSCs is decreased due to the decreased hole concentration. The results suggest that SnO film deposited at low substrate temperature holds promise for facilitating high-performance PSCs as HTMs.

Recent progress of graphene‐based materials for efficient charge transfer and device performance stability in perovskite solar cells

The relevance of graphene-based materials throughout the niche area of perovskite solar cells (PSCs) is indeed the main focus of this review. Specific properties of two types of solar cell materials, namely hybrid perovskites and graphene-based materials are at the core of significant breakthroughs in a wide range of applications. The specific features of graphene-based materials, along with their unique properties, have been utilized mainly in the development of photovoltaic devices. PSCs are known to have promising device performance and surpass other third-generation solar cells, including organic photovoltaics, quantum dot solar cells, and dye-sensitized solar cells. However, PSCs address several limitations in the device mechanism and material stability. PSCs performance tends to deplete over time due to several factors such as the degradation of materials used in the device caused by exposure of thermal and moisture, as well as an undesired chemical reaction in the interfaces. Several experimental studies, especially on the integration of carbon materials, including the graphene, have been extensively explored. The integration of graphene-based materials is one of the potential methods for altering and modifying components in PSCs, including perovskite structure and charges transport layers. Therefore, this review gives an overview of recent progress in the development of PSCs with the integration of graphene-based materials. The emphasis will be on the influence brought by graphene-based materials on the charge transport mechanism at the interfaces and perovskite morphology toward the improvement of photovoltaic performance and stability.

Teaching an Old Anchoring Group New Tricks: Enabling Low-Cost, Eco-Friendly Hole-Transporting Materials for Efficient and Stable Perovskite Solar Cells.

As a key component in perovskite solar cells (PVSCs), hole-transporting materials (HTMs) have been extensively explored and studied. Aiming to meet the requirements for future commercialization of PVSCs, HTMs which can enable excellent device performance with low cost and eco-friendly processability are urgently needed but rarely reported. In this work, a traditional anchoring group (2-cyanoacrylic acid) widely used in molecules for dye-sensitized solar cells is incorporated into donor-acceptor-type HTMs to afford MPA-BT-CA, which enables effective regulation of the frontier molecular orbital energy levels, interfacial modification of an ITO electrode, efficient defect passivation toward the perovskite layer, and more importantly alcohol solubility. Consequently, inverted PVSCs with this low-cost HTM exhibit excellent device performance with a remarkable power conversion efficiency (PCE) of 21.24% and good long-term stability in ambient conditions. More encouragingly, when processing MPA-BT-CA films with the green solvent ethanol, the corresponding PVSCs also deliver a substantial PCE as high as 20.52% with negligible hysteresis. Such molecular design of anchoring group-based materials represents great progress for developing efficient HTMs which combine the advantages of low cost, eco-friendly processability, and high performance. We believe that such design strategy will pave a new path for the exploration of highly efficient HTMs applicable to commercialization of PVSCs.

Enhancing the Interface Contact of Stacking Perovskite Solar Cells with Hexamethylenediammonium Diiodide-Modified PEDOT:PSS as an Electrode.

As an indispensable component of perovskite solar cells (PSCs), the commonly used Au and Ag electrodes still have some problems such as high cost and instability issues with regard to being corroded by iodide ions. In this paper, we report stacking perovskite solar cells (S-PSCs), which can avoid the use of precious metal electrodes and reduce the cost of devices and the requirements of equipment compared to conventional PSCs. The S-PSCs are composed of two semicells: a photoanode and a counter electrode (CE). For stacked devices, effective contact of the photoanode/CE interface is very important to the performance of the device. We used poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) as the electrode and modified it by hexamethylenediammonium diiodide (HDADI2) to improve its physical and electrical properties. The surface of the HDADI2-modified PEDOT:PSS becomes rough and achieves higher adhesion, which enables the photoanode and CE to be sufficiently connected. In addition, the energy-level structure of the HDADI2-modified PEDOT:PSS matches better with that of the adjacent functional layers. Therefore, the S-PSCs performance has been significantly improved. Under an illumination area of 1 cm2, the power-conversion efficiency (PCE) of the S-PSCs can reach 15.21%. Moreover, the S-PSCs can be disassembled and assembled flexibly and repeatedly disassembled 500 times with almost no change in the PCE. This has a positive impact on cell maintenance and modular production.

ZnO-Modified Anode for High-Performance SnO2-Based Planar Perovskite Solar Cells

Electron-transport layer (ETL) that promotes charge carrier separation and electron extraction is a key component of perovskite solar cells (PSCs). Here, we report a simple approach for improving c...

Efficient Planar Perovskite Solar Cells via a Sputtered Cathode

Perovskite solar cells (PSCs) attract great attention due to their low cost and high efficiency. In general, the Au cathode, a key component in PSCs, is prepared via an uneconomic vacuum thermal deposition method. Instead, the sputtering deposition method is much more economic and faster. However, it is generally thought that the organic hole transport layer such as 2,2′,7,7′‐tetrakis[N,N‐di(4‐methoxyphenyl)amino]‐9,9′‐spirobifluorene (Spiro‐OMeTAD) can be easily damaged by the high energy plasma during the sputtering process. Thus, the performance of the PSCs greatly decreases. Herein, the structure of the planar PSCs is carefully manipulated by matching the thickness of Spiro‐OMeTAD layer and the Au film. With the further engineering of the interface of the Au/Spiro‐OMeTAD, the planar PSCs with the sputtered Au cathode exhibit a highly reproducible average efficiency of 17.6% ± 0.8%, with the best efficiency of 18.3%. In addition, the Cu electrode is demonstrated by the sputtering method. Finally, the Au sputter deposition is scaled up to make a high efficiency (14.7%) 10 × 10 cm2 module. This demonstrates well that the sputtering deposition of the metal cathode is an effective way for the fabrication of high efficient PSCs for future industrialization.

Unveiling the Role of tBP-LiTFSI Complexes in Perovskite Solar Cells.

Lead halide-based perovskite materials have been applied as an intrinsic layer for next-generation photovoltaic devices. However, the stability and performance reproducibility of perovskite solar cells (PSCs) needs to be further improved to match that of silicon photovoltaic devices before they can be commercialized. One of the major bottlenecks that hinders the improvement of device stability/reproducibility is the additives in the hole-transport layer, lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and 4- tert-butylpyridine (tBP). Despite the positive effects of these hole-transport layer additives, LiTFSI is hygroscopic and can adsorb moisture to accelerate the perovskite decomposition. On the other hand, tBP, the only liquid component in PSCs, which evaporates easily, is corrosive to perovskite materials. Since 2012, the empirical molar ratio 6:1 tBP:LiTFSI has been wildly applied in PSCs without further concerns. In this study, the formation of tBP-LiTFSI complexes at various molar ratios has been discovered and investigated thoroughly. These complexes in PSCs can alleviate the negative effects (decomposition and corrosion) of individual components tBP and LiTFSI while maintaining their positive effects on perovskite materials. Consequently, a minor change in tBP:LiTFSI ratio results in huge influences on the stability of perovskite. Due to the existence of uncomplexed tBP in the 6:1 tBP:LiTFSI mixture, this empirical tBP-LiTFSI molar ratio has been demonstrated not as the ideal ratio in PSCs. Instead, the 4:1 tBP:LiTFSI mixture, in which all components are complexed, shows all positive effects of the hole-transport layer components with dramatically reduced negative effects. It minimizes the hygroscopicity of LiTFSI, while lowering the evaporation speed and corrosive effect of tBP. As a result, the PSCs fabricated with this tBP:LiTFSI ratio have the highest average device efficiency and obviously decreased efficiency variation with enhanced device stability, which is proposed as the golden ratio in PSCs. Our understanding of interactions between hole-transport layer additives and perovskite on a molecular level shows the pathway to further improve the PSCs' stability and performance reproducibility to make them a step closer to large-scale manufacturing.