Commercialization Of Perovskite Solar Cells Research Articles

Perovskite materials with improved stability and environmental friendliness for photovoltaics

Finding innovative, stable, and environmentally acceptable perovskite (PVK) sunlit absorber constituents has developed a major area of study in photovoltaics (PVs). As an alternative to lead-based organic-inorganic halide PVKs, these PVKs are being researched for use in cutting-edge PVK solar cells. While there has been progress in this field as of late, there are still several scientific and technical questions that have yet to be answered. Here, we offer insights into the big picture of PVK toxicity/instability research, and then we discuss methods for creating stable, non-toxic PVKs from scratch. It is also believed that the processing of the proposed PVKs, which occurs between materials design and actual devices, poses novel challenges. PVK PVs that are both stable and ecologically benign can be created if these topics receive more attention. It is interesting to note that although perovskite solar cells (PSCs) have impressive power conversion efficiency, their commercial adoption is hindered by lead toxicity. Lead is a hazardous material that can cause harm to humans and the environment. As a result, researchers worldwide are exploring non-toxic lead-free photovoltaics (PSCs) for a sustainable and safe environment. To achieve this goal, lead in PSCs is replaced by non-toxic or less harmful metals such as tin, germanium, titanium, silver, bismuth, and copper. A study has been conducted that provides information on the characteristics, sustainability, and obstacles of replacing lead with these metals in PSCs. The paper also explores solutions for stability and efficiency issues in lead-free, non-toxic PSC commercialization, including altering manufacturing techniques and adding additives. Lastly, it covers the latest developments/future perspectives in lead-free perovskite solar cells that can be implemented in lead-free PSCs.

Building Scalable Buried Interface for High‐Performance Perovskite Photovoltaic Devices

AbstractThe quality of the buried interface plays a key role in achieving high‐performance perovskite solar cells (PSCs). However, it is challenging to guarantee its quality on a larger area, which is pivotal for the commercialization of PSCs. Here, a facile strategy is developed to modify the SnO2/perovskite buried interface by incorporating L‐Aspartic acid monosodium salt (ASP‐Na) into SnO2 colloidal dispersion. ASP‐Na with multidentate ligands can coordinate with Sn to form stable dispersion, inhibiting the agglomeration of nanoparticles at the buried interface. In addition, the coordination between ASP‐Na and SnO2 nanoparticles in turn promotes the uniform distribution of ASP‐Na, which facilitates the uniform and effective passivation of the buried defects. Consequently, the ASP‐Na treatment improves the device efficiency from 23.44% to 25.47% (certified 25.02%) with an aperture area of 0.0797 cm2 without hysteresis and enhances the operation stability. The perovskite mini‐module achieves an efficiency of 20.11% with an aperture area of 18.30 cm2, demonstrating the potential of the strategy for scalability.

The issues on the commercialization of perovskite solar cells

Abstract Perovskite solar cells have aroused a worldwide research upsurge in recent years due to their soaring photovoltaic performance, ease of solution processing, and low cost. The power conversion efficiency record is constantly being broken and has recently reached 26.0% in the lab, which is comparable to the established photovoltaic technologies such as crystalline silicon, copper indium gallium selenide (CIGS) and cadmium telluride (CdTe) solar cells. Currently, perovskite solar cells are standing at the entrance of industrialization, where huge opportunities and risks coexist. However, towards commercialization, challenges of up-scaling, stability and lead toxicity still remain, the proper handling of which could potentially lead to the widespread adoption of perovskite solar cells as a low-cost and efficient source of renewable energy. This review gives a holistic analysis of the path towards commercialization for perovskite solar cells. A comprehensive overview of the current state-of-the-art level for perovskite solar cells and modules will be introduced first. We will then discuss the challenges that get in the way of commercialization, and provide insights into the future direction of commercialization of perovskite photovoltaics.

Cascade Reaction in Organic Hole Transport Layer Enables Efficient Perovskite Solar Cells.

The doped organic hole transport layer (HTL) is crucial for achieving high-efficiency perovskite solar cells (PSCs). However, the traditional doping strategy undergoes a time-consuming and environment-dependent oxidation process, which hinders the technology upgrades and commercialization of PSCs. Here, we reported a new strategy by introducing a cascade reaction in traditional doped Spiro-OMeTAD, which can simultaneously achieve rapid oxidation and overcome the erosion of perovskite by 4-tert-butylpyridine (tBP) in organic HTL. The ideal dopant iodobenzene diacetate was utilized as the initiator that can react with Spiro to generate Spiro•+ radicals quickly and efficiently without the participation of ambient air, with the byproduct of iodobenzene (DB). Then, the DB can coordinate with tBP through a halogen bond to form a tBP-DB complex, minimizing the sustained erosion from tBP to perovskite. Based on the above cascade reaction, the resulting Spiro-based PSCs have a champion PCE of 25.76% (certificated of 25.38%). This new oxidation process of HTL is less environment-dependent and produces PSCs with higher reproducibility. Moreover, the PTAA-based PSCs obtain a PCE of 23.76%, demonstrating the excellent applicability of this doping strategy on organic HTL.

Cascade Reaction in Organic Hole Transport Layer Enables Efficient Perovskite Solar Cells

The doped organic hole transport layer (HTL) is crucial for achieving high‐efficiency perovskite solar cells (PSCs). However, the traditional doping strategy undergoes a time‐consuming and environment‐dependent oxidation process, which hinders the technology upgrades and commercialization of PSCs. Here, we reported a new strategy by introducing a cascade reaction in traditional doped Spiro‐OMeTAD, which can simultaneously achieve rapid oxidation and overcome the erosion of perovskite by 4‐tert‐butylpyridine (tBP) in organic HTL. The ideal dopant iodobenzene diacetate was utilized as the initiator that can react with Spiro to generate Spiro•+ radicals quickly and efficiently without the participation of ambient air, with the byproduct of iodobenzene (DB). Then, the DB can coordinate with tBP through a halogen bond to form a tBP‐DB complex, minimizing the sustained erosion from tBP to perovskite. Based on the above cascade reaction, the resulting Spiro‐based PSCs have a champion PCE of 25.76% (certificated of 25.38%). This new oxidation process of HTL is less environment‐dependent and produces PSCs with higher reproducibility. Moreover, the PTAA‐based PSCs obtain a PCE of 23.76%, demonstrating the excellent applicability of this doping strategy on organic HTL.

Smart Materials to Empowering Perovskite Solar Cells with Self‐Healing Capability

Inspired by nature, intelligent self‐healing materials have recently been exploited also in the field of photovoltaics to mimic natural systems achieving self‐repairing. The past decade has witnessed perovskite solar cells (PSCs) skyrocketing to a certified power conversion efficiency of 26.1%. However, their intrinsic instability, when exposing to moisture, high temperature, and continuous illumination, hampers their commercial development for a long‐term use in ambient operating conditions. Therefore, the use of smart self‐healing materials, based on self‐assembling properties and dynamic interactions, empowers PSCs with self‐recovery abilities to reinforce their pivotal role as efficient photovoltaic devices and encourage their exploitation in the market. Herein, the current progress in self‐healing perovskite materials with a special focus on self‐recovery after moisture exposure or mechanical damage with the aim to provide a valuable insight for research on this topic to accelerate the PSC commercialization process is highlighted.

Co-solvent strategy for highly efficient perovskite solar cells by spray coating

The ultrasonic spray coating has been shown to be an effective technique for scaling up production. The nucleation and crystallization process of the perovskite film prepared by the ultrasonic spraying approach is more complicated than that by the spin coating, but they are essential to gaining efficient perovskite solar cells (PSCs). At the same time, the green solvent is the primary problem that must be solved in the process of PSCs commercialization. In this paper, the low boiling point and green solvent isopropyl alcohol (IPA) is introduced into the perovskite precursor solution to prepare FAPbI3 perovskite by ultrasonic spraying. The addition of IPA enhanced the saturated vapor pressure of the precursor solution, which can create the local chemical microenvironment on the film surface and subsequently retard the nucleation rate from 8.31 s to 8.54 s at nucleation stage. The local chemical improves the initial homogeneity of the sol–gel phase and then leads to improved structural and optoelectronic properties within the FAPbI3 film via sufficient crystallization from the sol–gel phase to α-FAPbI3. Ultimately, IPA-based PSCs exhibit the champion device efficiency of 22.43 %. The good long-term stability of PSCs (maintain more than 90 % of the initial efficiency after 1000 h, and keep 80 % after 400 h) in ambient conditions.

Green-solvent processable polymeric hole transport materials with functional groups for inverted perovskite solar cell

Exploring novel hole transport materials (HTMs) with high hole mobility and eco-friendly processability are imperative for the commercialization of perovskite solar cells (PSCs). However, there is a ‘trade-off’ that the introduction of large-conjugated units aiming to ensure high hole mobility, inevitably compromises the green-solvent solubility of HTMs. In this work, a hybrid strategy of rigidity and flexibility is proposed, in which the conjugated unit is assembled by the rigid binaphthylamine core, and the amide-bond constitutes the flexible backbone. Polar solubilizing units ethylenedioxythiophene and thiophene are used as bridges to construct two kinds of polymers, cited as EDOT-SMe and T-SMe, respectively. Both polymers achieve high hole mobility, well-matched energy levels and efficient defect passivation effect toward the perovskite films. When processing the HTM films with the green solvent (2-methylanisole), the corresponding PSCs deliver fill factors as high as 82.7% for EDOT-SMe and 81.9% for T-SMe, respectively. Consequently, power conversion efficiencies of 20.25% for EDOT-SMe and 20.09% for T-SMe are realized, outperforming that of commercial polymer poly[bis(4-phenyl) (2,4,6-trimethylphenyl)amine] (PTAA, 19.71%). Moreover, PSCs with these polyamides achieve good long-term stability. This work paves a new path for exploring efficient and green-solvent processable polymeric HTMs.

Efficient Inverted Perovskite Photovoltaics Through Surface State Manipulation.

Inverted perovskite solar cells (PSCs) are considered as the most promising avenue for the commercialization of PSCs due to their potential inherent stability. However, suboptimal interface contacts between electron transport layer (ETL) (such as C60 ) and the perovskite absorbing layer within inverted PSCs always result in reduced efficiency and poor stability. Herein, a surface state manipulation strategy has been developed by employing a highly electronegative 4-fluorophenethylamine hydrochloride (p-F-PEACl) to effectively address the issue of poor interface contacts in the inverted PSCs. The p-F-PEACl demonstrates a robust interaction with perovskite film through bonding of amino group and Cl- with I- and Pb2+ ions in the perovskite, respectively. As such, the surface defects of perovskite film can be significantly reduced, leading to suppressed non-radiative recombination. Moreover, p-F-PEACl also plays a dual role in enhancing the surface potential and improving energy-level alignment at the interfaces between the perovskite and C60 carrier transport layer, which directly contributes to efficient charge extraction. Finally, the open-circuit voltage (Voc ) of devices increases from 1.104 V to 1.157V, leading to an overall efficiency improvement from 22.34% to 24.78%. Furthermore, the p-F-PEACl-treated PSCs also display excellent stability.

Multifunctionally Reusing Waste Solder to Prepare Highly Efficient Sn-Pb Perovskite Solar Cells.

The preparation of perovskite components (PbI2 and SnI2 ) using waste materials is of great significance for the commercialization of perovskite solar cells (PSCs). However, this goal is difficult to achieve due to the purity of the recovered products and the easy oxidation of Sn2+ . Here, a simple one-step synthetic process to convert waste Sn-Pb solder into SnI2 /PbI2 and then applied as-prepared SnI2 /PbI2 to PSCs for high additional value is adopted. During fabrication, Sn-Pb waste solder is also employed to serve as a reducing agent to reduce the Sn4+ in Sn-Pb mixed narrow perovskite precursor and hence remove the deep trap states in perovskite. The target PSCs achieved an efficiency of 21.04%, which is better than the efficiency of the device with commercial SnI2 /PbI2 (20.10%). Meanwhile, the target PSC maintained an initial efficiency of 80% even after 800h under continuous illumination, which is significantly better than commercial devices. In addition, the method achieved a recovery rate of 90.12% for Sn-Pb waste solder, with a lab-grade purity (over 99.8%) for SnI2 /PbI2 , and the cost of perovskite active layer reduced to 39.81% through this recycling strategy through calculation.

Multifunctional Trifluoroborate Additive for Simultaneous Carrier Dynamics Governance and Defects Passivation to Boost Efficiency and Stability of Inverted Perovskite Solar Cells

AbstractThe main obstacles to promoting the commercialization of perovskite solar cells (PSCs) include their record power conversion efficiency (PCE), which still remains below the Shockley–Queisser limit, and poor long‐term stability, attributable to crystallographic defects in perovskite films and open‐circuit voltage (Voc) loss in devices. In this study, potassium (4‐tert‐butoxycarbonylpiperazin‐1‐yl) methyl trifluoroborate (PTFBK) was employed as a multifunctional additive to target and modulate bulk perovskite defects and carrier dynamics of PSCs. Apart from simultaneously passivating anionic and cationic defects, PTFBK could also optimize the energy‐level alignment of devices and weaken the interaction between carriers and longitudinal optical phonons, resulting in a carrier lifetime of greater than 3 μs. Furthermore, it inhibited non‐radiative recombination and improved the crystallization capacity in the target perovskite film. Hence, the target rigid and flexible p‐i‐n PSCs yielded champion PCEs of 24.99 % and 23.48 %, respectively. More importantly, due to hydrogen bonding between formamidinium and fluorine, the target devices exhibited remarkable thermal, humidity, and operational tracking at maximum power point stabilities. The reduced Young's modulus and residual stress in the perovskite layer also provided excellent bending stability for flexible target devices.

Multifunctional Trifluoroborate Additive for Simultaneous Carrier Dynamics Governance and Defects Passivation to Boost Efficiency and Stability of Inverted Perovskite Solar Cells.

The main obstacles to promoting the commercialization of perovskite solar cells (PSCs) include their record power conversion efficiency (PCE), which still remains below the Shockley-Queisser limit, and poor long-term stability, attributable to crystallographic defects in perovskite films and open-circuit voltage (Voc) loss in devices. In this study, potassium (4-tert-butoxycarbonylpiperazin-1-yl) methyl trifluoroborate (PTFBK) was employed as a multifunctional additive to target and modulate bulk perovskite defects and carrier dynamics of PSCs. Apart from simultaneously passivating anionic and cationic defects, PTFBK could also optimize the energy-level alignment of devices and weaken the interaction between carriers and longitudinal optical phonons, resulting in a carrier lifetime of greater than 3 μs. Furthermore, it inhibited non-radiative recombination and improved the crystallization capacity in the target perovskite film. Hence, the target rigid and flexible p-i-n PSCs yielded champion PCEs of 24.99 % and 23.48 %, respectively. More importantly, due to hydrogen bonding between formamidinium and fluorine, the target devices exhibited remarkable thermal, humidity, and operational tracking at maximum power point stabilities. The reduced Young's modulus and residual stress in the perovskite layer also provided excellent bending stability for flexible target devices.

Slot‐Die‐Deposition of CuSCN Using Asymmetric Alkyl Sulfides as Co‐Solvent for Low‐Cost and Fully Scalable Perovskite Solar Cell Fabrication

The development of industrially relevant deposition processes for efficient, stable, and inexpensive charge extracting layers is crucial for the commercialization of perovskite solar cells (PSC). This work demonstrates, for the first time, the deposition of copper thiocyanate (CuSCN) as a low‐cost and reliable hole transport layer using slot‐die‐coating. Methyl ethyl sulfide (MES) is thereby used as an asymmetric co‐solvent to significantly increase the solubility of CuSCN in the utilized slot‐die ink compared to traditional pure diethyl sulfide (DES) based solutions. Optimized CuSCN inks allow for the deposition of CuSCN layers on 5 × 10 cm2 substrates with a wide range of thicknesses. Multidimensional imaging photoluminescence techniques are used to investigate the uniformity of the CuSCN thin films deposition as well as the influence of the solvent on charge losses. Finally, the CuSCN slot‐die deposition is integrated into a fully up‐scalable PSC fabrication process showing 19.1% power conversion efficiency for small laboratory cells and 14.7 % for 9 cm2 mini‐modules. Furthermore, semi‐transparent mini modules retained 80% of their initial efficiency after 500h of constant illumination.This article is protected by copyright. All rights reserved.

Ultrasonic‐Assisted Processing Combined with Gas Quenching for Fabricating High‐Performance and Stable Inverted Perovskite Solar Cells

AbstractIn recent years, perovskite solar cells have attained unprecedented advancements in power conversion efficiency, yet their commercialization remains a formidable challenge. Addressing this challenge relies on developing an affordable and scalable method for manufacturing top‐notch perovskite films. This study presents an innovative strategy, employing both gas quenching technology and ultrasonic‐assisted processing (UAP), to fabricate high‐caliber perovskite thin films. The UAP process enhances the grain size of the perovskite film, reduces grain boundary defects, improves carrier extraction and transport, and suppresses carrier nonradiative recombination. Furthermore, it effectively reduces residual stress and mitigates lattice distortion in the perovskite crystals. Ultimately, efficient and stable inverted perovskite solar cells using FA0.87Cs0.13PbI2.7Br0.3 and FA0.85MA0.1Cs0.05PbI3 perovskite are successfully prepared. The target device achieved a power conversion efficiency of 22.32% and 24.51%, respectively. Moreover, the target devices exhibited enhanced photostability. This work provides a cost‐effective and scalable method for producing high‐quality perovskite films, paving the way for the commercialization of perovskite solar cells.

Application of Carbon Materials in Conductive Electrodes for Perovskite Solar Cells

Over the past decade, perovskite solar cells (PSCs) have achieved significant achievements. But the golden triangle problem of commercial development, which encompasses high efficiency, high stability, and low cost, remains unresolved. Carbon materials exhibit a diverse range of morphological structures and possess numerous advantages. They are extensively used in PSCs to overcome the challenges encountered during PSCs commercialization. The PSCs utilizing graphene as the top electrodes not only deliver an impressive efficiency of 22.8%, but also show exceptional long‐term stability. The PSCs using carbon nanotubes as transparent conductive electrodes obtain an efficiency of 19%, exhibiting significant potential for scalable applications. Herein, the advantages of carbon materials as conductive electrodes are overviewed. The compatibility of carbon materials as conductive electrodes in PSCs, along with the associated challenges, regulatory strategies, and device performance are systematically discussed in terms of their intrinsic characteristics. The application of carbon materials derived from petroleum by‐products and biomass in the top electrodes of PSCs are summarized in detail. Finally, the underlying reasons why PSCs using carbon electrode show a comparatively lower efficiency when compared to conventional devices is analyzed in‐depth. The potential research directions are proposed to promote the development of carbon conductive electrodes in PSCs.

Conjugated Phosphonic Acids Enable Robust Hole Transport Layers for Efficient and Intrinsically Stable Perovskite Solar Cells.

High efficiency and long-term stability are the prerequisites for the commercialization of perovskite solar cells (PSCs). However, inadequate and non-uniform doping of hole transport layers (HTLs) still limits the efficiency improvements, while the intrinsic instability of HTLs caused by ion migration and accumulation is difficult to be addressed by external encapsulation. Here it is shown that the addition of a conjugated phosphonic acid (CPA) to the Spiro-OMeTAD benchmark HTL can greatly enhance the device efficiency and intrinsic stability. Featuring an optimal diprotic-acid structure, indolo(3,2-b)carbazole-5,11-diylbis(butane-4,1-diyl) bis(phosphonic acid) (BCZ) is developed to promote morphological uniformity and mitigate ion migration across both perovskite/HTL and HTL/Ag interfaces, leading to superior charge conductivity, reinforced ion immobilization, and remarkable film stability. The dramatically improved interfacial charge collection endows BCZ-based n-i-p PSCs with a champion power conversion efficiency of 24.51%. More encouragingly, the BCZ-based devices demonstrate remarkable stability under harsh environmental conditions by retaining 90% of initial efficiency after 3000h in air storage. This work paves the way for further developing robust organic HTLs for optoelectronic devices.

Doping strategies for inorganic lead-free halide perovskite solar cells: progress and challenges.

In recent years, remarkable advancements have been achieved in the field of halide perovskite solar cells (PSCs). However, the commercialization of PSCs has been impeded by challenges such as Pb leakage and the instability of hybrid organic-inorganic perovskites (HOIPs). Hence, the future lies in the development of environmentally friendly inorganic lead-free halide perovskites (LFHPs) based on elements like Sn, Ge, Bi, Sb, and Cu, which show great promise for photovoltaic applications. However, LFHP photovoltaic cells still face challenges such as low efficiency, poor film quality, and stability in comparison to HOIPs. These limitations significantly hinder their further development. To address these issues, element doping strategies, including cationic and anionic doping, as well as the use of additives, are frequently employed. These strategies aim to improve film quality, passivate defects, reduce the band gap, and enhance device performance and stability. In this paper, we aim to provide a comprehensive review of the recent research progress in doping strategies for LFHPs.

Impact of hole-transport layer materials on the field-induced degradation of p-i-n perovskite solar cells

The choice of hole-transport materials (HTMs) has a strong impact on electric field-induced degradation of perovskite solar cells (PSCs). Rational design of HTMs is necessary to make PSCs sufficiently stable for the targeted practical applications.

Fullerene-C60 and PCBM as interlayers in regular and inverted lead-free PSCs using CH3NH3SnI3: an analysis of device performance and defect density dependence by SCAPS-1D.

One of the challenges hindering the commercialization of perovskite solar cells (PSCs) is the presence of toxic metals such as lead in their composition. Simulation studies using SCAPS-1D have already been conducted on lead-free PSCs to find optimized solar cell parameters, having tin as the primary candidate for replacing lead in perovskites. Here, we used fullerene-C60 and its derivative PCBM as interlayers in a lead-free tin-based PSC between the ETL (ZnO) and the perovskite MASI in both regular and inverted configurations of PSCs using SCAPS-1D software. To the best of our knowledge, this is the first simulation study reporting the impact of using fullerene-C60 and PCBM as interlayers in lead-free PSCs. The defect density (Nt) of the perovskite material is varied, allowing us to observe its influence on the power conversion efficiency (PCE). Using an Nt value of 1017 cm-3 without the interlayer, the PCE was 6.90% and 3.72% for regular and inverted devices. Using PCBM as an interlayer improves the efficiency of both simulated PSCs, achieving a maximum PCE of 8.11% and 5.26% for the regular and inverted configurations, respectively. Decreasing the Nt from 1017 cm-3 to 1016 cm-3 caused a significant increase in efficiency, reaching 13.38% (n-i-p) and 10.00% (p-i-n). Finally, using the optimized parameters and an ideal Nt value (1013 cm-3), both PSCs achieved a PCE close to 30%.

The impact of moisture on the stability and degradation of perovskites in solar cells

Efficiency and stability are the two most important factors in commercially scalable solar cells.