Methylammonium Iodide Research Articles

Discovery, synthesis, and anti-cancer evaluation of 10-Pterostilbene methylamine hydrochloride derivatives as potential COX-2 and Topo I dual inhibitors

A series of (E)-N-benzyl-1-(2, 4-dimethoxy-6-(4 methoxystyryl) phenyl) methanamine (DMPM) derivatives (D1-D25) were successfully synthesized in the form of hydrochloride, and characterized by spectroscopic techniques. The structure of D15 was further confirmed by X-ray single crystal diffraction, where D15 existed in the form of a dimer constructed by intermolecular hydrogen bonds between the active hydrogen of –NH2+− and Cl−, and the –CH=CH– in the molecule was identified as E configuration. Compounds were evaluated for their anti-cancer properties toward HepG2, Eac-109 and MDA-MB-231 cell lines in vitro. Meanwhile, bioactive compound's toxicity against L02 cell lines were also tested. Sixteen compounds (D2, D5-D8, D10, D13, D16-D23, and D25) exhibited significant cytotoxicity against tested cancer cells with IC50 values ranging from 4.13 to 36.77 μM/L. Their toxicity toward normal human liver cells was lower than that of Cisplatin. Among them, D10, D20 and D25 showed more potent anti-cancer abilities than others. Especially, D20 manifested anti-cancer effects comparable to Cisplatin on all tested cancer cell lines. SAR revealed that –OCH2CH(CH3)2 or –O(CH2)3CH3 substitution (R1) on the benzene ring of Pterostilbene is key factors in enhancing biological activities, while –OCH3, –Cl or –F substitution (R2) on another benzene ring is beneficial for improving anti-cancer abilities, and –OCH3 may be the most favorable modifying groups for enhancing skeleton's activities. Bioactive compounds displayed excellent inhibitory effects on COX-2 at nanomolar concentrations. D20 (IC50 (COX-2) = 69.92 nm/L) was identified as the most promising COX-2 inhibitor, meanwhile, it also exhibited significant Topo I inhibitory ability at 20 μM/L. In addition, D20 effectively docked to COX-2 (PDB: 5KIR) and Topo I protein (PDB: 1TBI) with affinity of -9.0 and -5.7 kcal/mol, respectively. As a potential COX-2 and Topo I dual inhibitor, D20 induced ROS-mediate mitochondria dysfunction and altered the expression of apoptosis related proteins such as Bcl-2, Bax, Caspase3/9, and P53, leading to significant apoptosis in HepG2 cells. Moreover, D20 markedly up-regulated P21, reduced the level of CDK4 or Cyclin D1, and caused G1 phase arrest on HepG2 cancer cell lines.

Methyl-ammonium lead iodide hybrid perovskite thin film as active material for energy conversion devices

The use of hybrid halide Perovskites is helping us get closer to our aim of completely selfsufficient structures in terms of energy production. Preparation of a device of photoactive material CH3NH3PbI3 {FTO (Fluorine-doped tin Oxide)/ CH3NH3PbI3/SpiroOMeTAD/Al} for the photovoltaic applications has been described in this article. Producing a homogeneous thin film through the use of lower temperature, processedsolution devices with one-step spin coating processes is an essential stage in the fabrication process. To generate the thin films on the FTO-substrate, the one-step spin coating approach was utilized for the deposition of the precursor solution, which consisted of methylammonium iodide and lead iodide in a molar ratio of 3:1. This technique was employed to prepare the thin films. The FESEM technique was utilized to carry out the investigation of the surface morphology of this thin layer. In addition, the essential parameters of this device, like barrier height, saturation current, current density, ideality factor, carrier mobility, resistance, carrier lifetime, and capacitance have been computed using current-voltage (I-V) characteristics and the impedance spectroscopy technique. A laser with a power of 20 milliwatts and a wavelength of 532 nanometers was used to light the gadget. The current conduction mechanism exhibits ohmic behavior at a low voltage, while at medium voltages, TFSCLC is the mechanism that regulates charge transportation. Despite the fact that TCSCLC is demonstrated at higher voltages. The TCSCLC model was used to conduct an investigation of the hole's mobility.

Iodine Modulates the MACl‐Assisted Growth of FAPbI3 for High Efficiency Perovskite Solar Cells

AbstractThe preferential growth of α‐phase formamidinium perovskite (α‐FAPbI3) at low temperatures can be achieved with the incorporation of chloride‐based additives, with methylammonium chloride (MACl) being the most common example. However, compared to other less‐volatile chloride additives, MACl only remains in the growing perovskite film for a short time before evaporating during annealing, primarily influencing the early stages of film formation. In addition, evaporation of MACl as methylamine (MA0) and HCl can introduce a side reaction between MA0 and formamidinium (FA), undermining the compositional purity and phase stability of α‐FAPbI3. In this study, it is demonstrated that addition of iodine (I2) into the FAPbI3 precursor solution containing MACl suppresses the MA‐FA side reaction during annealing. Additionally, MACl evaporation is delayed owing to strong interaction with triiodide. The added I2 facilitates spontaneous growth of α‐FAPbI3 prior to annealing, with an improved bottom morphology due to the formation of fewer byproducts. Perovskite solar cells derived from an I2‐incorporated solution deliver a champion power conversion efficiency of 25.2% that is attributed to suppressed non‐radiative recombination.

Unraveling the Influence of Solvent on Side Reactions between Formamidinium Lead Triiodide and Methylammonium Cations.

Formamidinium lead triiodide (FAPbI3) perovskite thin films are commonly deposited through a solution process, often incorporating a specific amount of methylammonium halide to stabilize the α-phase or enhance their crystallinity. The precursor solution for such coatings significantly influences the fabrication of perovskite solar cells (PSCs), involving time-dependent aging and byproduct formation. The chemical principle underlying this behavior is believed to be related to the deprotonation of methylamine cations (MA+) and subsequent chemical reactions with FA+ to generate N-methylformamidinium. Nevertheless, the role of the solvent in the side reactions between these organic cations remains unclear. This work systematically investigates the reaction reactivity in three protic solvents and three aprotic solvents. We uncover the hidden role of dimethylamine from the hydrolysis products of N,N-dimethylformamide, promoting the reaction between FA+ and MA+. Additionally, we elucidate the impact of environmental factors, such as water and oxygen, in stabilizing precursor solutions. This work establishes a basic concept and scientific direction for rationalizing high-efficiency, reproducible, and long-term-stable PSCs.

Achieving Well-Oriented FAPbI3 Perovskite Photovoltaics by Cyclohexane Modification.

It is essential and challenging to develop green and cost-effective solar cells to meet the energy demands. Solar cells with a perovskite light-harvesting layer are the most promising technology to propel the world toward next-generation solar energy. Formamidinium lead tri-iodide (FAPbI3)-based perovskite solar cells (F-PSCs), with their considerable performance, offer cost-effective solar cells. One of the major issues that the PSC community is now experiencing is the stability of α-FAPbI3 at relatively low temperatures. In this study, we fabricated FAPbI3-PSCs using cyclohexane (CHX) material via a two-step deposition method. For this purpose, CHX is added to the formamidinium iodide:methylammonium chloride (FAI:MACl) solution as an additive and used to form a better FAPbI3 layer by controlling the reaction between FAI and lead iodide (PbI2). The CHX additive induces the reaction of undercoordinated Pb2+ with FAI material and produces an α-FAPbI3 layer with low charge traps and large domains. In addition, the CHX-containing FAPbI3 layers show higher carrier lifetimes and facilitate carrier transfer in F-PSCs. The CHX-modified F-PSCs yield a high champion efficiency of 22.84% with improved ambient and thermal stability behavior. This breakthrough provides valuable findings regarding the formation of a desirable FAPbI3 layer for photovoltaic applications and holds promise for the industrialization of F-PSCs.

Ge-doped Sn-Pb assisted by MACl triple metal cation perovskite solar cells with high open-circuit voltage

The potential to achieve the best photovoltaic properties by incorporating Ge into Sn-Pb-based perovskites (PVKs) is theoretically plausible. However, practical implementation is hindered by critical obstacles associated with Ge-containing precursors, such as poor solubility and extremely low stability. Furthermore, the application of Ge in PVKs is limited, particularly when combined with Sn-Pb-based PVK, owing to the instability of Sn and Ge within the same precursor. Herein, we report a groundbreaking method for inserting Ge into Sn-Pb PVK using volatile additives, resulting in high-performance Sn-Pb-Ge triple metal cation PVK solar cells (PSCs). Adding methylammonium chloride facilitates the dissolution of germanium iodide (GeI2) through anion exchange in the precursor, which evaporates during high-temperature annealing after the formation of the PVK films. The resulting low-bandgap PVK (1.228 eV), containing 3 % Ge, exhibits increased grain sizes and a significantly improved open-circuit voltage of 0.834 V, which can be attributed to a reduced energetic offset. The Sn-Pb-Ge triple metal cation PSC exhibits a power conversion efficiency of 20.7 % and enhanced stability.

Unraveling Bulk versus Surface Passivation Effects in Highly Efficient p–i–n Perovskite Solar Cells Using Thiophene‐Based Cations

Defect passivation is nowadays considered a must‐have route for high‐efficiency perovskite solar cells. However, a general rule that correlates the choice of passivating agents with performance enhancements is still missing. Herein, two different thiophene salts that are used as passivating agents are compared, namely thiophene methylammonium chloride and thiophene ethylammonium chloride (TEACl), which are used for the passivation of bulk and surface defects in triple‐cation‐based metal halide perovskites. First, it is observed that the surface passivation method leads to better device performances reaching a power conversion efficiency of 23.56%, with reduced voltage losses and increased fill factor when compared with the reference. Second, it is demonstrated that the chemical structure of the cation dictates its capability either in passivating bulk defects effectively or to form a superficial two‐dimensional/three‐dimensional heterostructure, which happens only for the TEACl case. The chemical composition and the cation dimension are responsible for device performance enhancement as observed by a joint spectroscopic and density functional theory simulations study, providing rational guidelines for further smart device design.

Anti‐Solvent‐Free Preparation for Efficient and Photostable Pure‐Iodide Wide‐Bandgap Perovskite Solar Cells

AbstractThe perovskite/silicon tandem solar cell (TSC) has attracted tremendous attention due to its potential to breakthrough the theoretical efficiency set for single‐junction solar cells. However, the perovskite solar cell (PSC) designed as its top component cell suffers from severe photo‐induced halide segregation owing to its mixed‐halide strategy for achieving desirable wide‐bandgap (1.68 eV). Developing pure‐iodide wide‐bandgap perovskites is a promising route to fabricate photostable perovskite/silicon TSCs. Here, we report efficient and photostable pure‐iodide wide‐bandgap PSCs made from an anti‐solvent‐free (ASF) technique. The ASF process is achieved by mixing two precursor solutions, both of which are capable of depositing corresponding perovskite films without involving anti‐solvent. The mixed solution finally forms Cs0.3DMA0.2MA0.5PbI3 perovskite film with a bandgap of 1.68 eV. Furthermore, methylammonium chloride additive is applied to enhance the crystallinity and reduce the trap density of perovskite films. As a result, the pure‐iodide wide‐bandgap PSC delivers efficiency as high as 21.30 % with excellent photostability, the highest for this type of solar cells. The ASF method significantly improves the device reproducibility as compared with devices made from other anti‐solvent methods. Our findings provide a novel recipe to prepare efficient and photostable wide‐bandgap PSCs.

Anti-Solvent-Free Preparation for Efficient and Photostable Pure-Iodide Wide-Bandgap Perovskite Solar Cells.

The perovskite/silicon tandem solar cell (TSC) has attracted tremendous attention due to its potential to breakthrough the theoretical efficiency set for single-junction solar cells. However, the perovskite solar cell (PSC) designed as its top component cell suffers from severe photo-induced halide segregation owing to its mixed-halide strategy for achieving desirable wide-bandgap (1.68 eV). Developing pure-iodide wide-bandgap perovskites is a promising route to fabricate photostable perovskite/silicon TSCs. Here, we report efficient and photostable pure-iodide wide-bandgap PSCs made from an anti-solvent-free (ASF) technique. The ASF process is achieved by mixing two precursor solutions, both of which are capable of depositing corresponding perovskite films without involving anti-solvent. The mixed solution finally forms Cs0.3DMA0.2MA0.5PbI3 perovskite film with a bandgap of 1.68 eV. Furthermore, methylammonium chloride additive is applied to enhance the crystallinity and reduce the trap density of perovskite films. As a result, the pure-iodide wide-bandgap PSC delivers efficiency as high as 21.30 % with excellent photostability, the highest for this type of solar cells. The ASF method significantly improves the device reproducibility as compared with devices made from other anti-solvent methods. Our findings provide a novel recipe to prepare efficient and photostable wide-bandgap PSCs.

Efficient Tin-Lead Perovskite Solar Cells with a Ultrawide Usage Windows of Precursor Solution Opened by SnF2.

High quality tin-lead perovskite solar cells (Sn─Pb PSCs) can be fabricated via simple solution processing methods. However, the instability of precursor solutions and their narrow usage windows still pose challenges in manufacturing efficient and reproducible Sn─Pb PSCs, hindering the commercialization of PSCs. Fluorine tin (SnF2) is widely used as an antioxidant to improve the crystallinity of perovskite. In this study, another role of SnF2 as a stabilizer is found to restrain the deprotonation of methylammonium iodide (MAI)in the precursor solution, which improves their stability and expands their usage windows. Due to the inhibition of SnF2 on oxidation and deprotonation, stable large-sized colloidal clusters form gradually in perovskite precursor solution during aging, leading to uniform nucleation/crystallization during film growth, significantly reducing the roughness and defect density in the films. Because of the competitive deprotonation and oxidation process of Sn2+, the benefit of larger cluster maximizes after about ten days storage of precursor solution. The champion efficiency of Sn─Pb PSCs prepared with 10days aged precursor solution is 22.00%. High performance of devices fabricated with precursor solution stored for even ≈40days discloses the wide usage windows of precursor solution with SnF2 additive.

Unlocking the potential of antisolvent-free perovskite solar cells: Modulating crystallization and intermediates through a binary volatile additive strategy

High-quality perovskite polycrystalline thin films are generally achieved through antisolvent-assisted crystallization, a crucial process that facilitates desolvation. However, antisolvent method is limited by issues of toxicity and fabrication complexity. Here, we introduce a “binary volatile additive” strategy using methylammonium chloride (MACl) and trifluoroacetamide (TFAA) in dimethylformamide/N-methyl-2-pyrrolidone co-solvent system, enabling end-to-end management of antisolvent-free crystallization process. Combining in-situ characterizations and DFT calculations, we prove that TFAA adjusts coordination with perovskite intermediates, facilitating solvent removal and promoting the formation of nuclei, while MACl reduces the formation energy of α-phase formamidinium-based perovskite. Moreover, TFAA not only releases the residual strain caused by MACl, but also in combination with MACl, synergistically widens crystallization window and regulates ripening process, allowing for precise fabrication of homogeneous perovskite films with suppressed defects. By employing the “binary volatile additive” approach, we achieve perovskite solar cells with a power conversion efficiency up to 22.4% and elongated storage life (93% PCE retention over 1000 hours). Our study offers a simple and sustainable approach to produce high-quality perovskite films without the acquisition of antisolvent, streamlining the fabrication process.

Investigation of MASnIxBr3−x (x = 3, 2, 1, 0) Perovskite Thin Films Produced by Ultrasonic Spray Pyrolysis Method

Methylammonium iodide (MAI) and methylammonium bromide (MABr) reactants were synthesized in powder form. Tin-based perovskites (MASnIxBr3−x (x = 3, 2, 1, 0)) were deposited as a thin film on glass substrates using the ultrasonic spray pyrolysis (USP) method. X-ray diffraction (XRD) was used to examine the crystallographic characteristics of the synthesized MAI/MABr powders and perovskite thin films. A shift occurred in the XRD peaks by changing the I/Br ratios. Morphological analysis of the MAI and MABr were carried out by scanning electron microscopy (SEM). While the average particle size was calculated a ~ 94 μm for MAI, it was obtained as ~ 188 μm for MABr. The Fourier transform infrared (FTIR) spectroscopy peaks observed for synthesized MAI and MABr were found to be compatible with commercial MAI and MABr FTIR peaks. Elemental analysis of MASnIxBr3−x (x = 3, 2, 1, 0) perovskite thin films was performed energy dispersive spectroscopy (EDS). Forbidden band gap (Eg) values of perovskite thin films were obtained from Tauc curves. The Eg value increased with an increasing I/Br ratio. The deposition of highly stoichiometric MASnIxBr3–x perovskites thin films was achieved by the USP method. This method has many parameters need to be optimized. This study gives optimum parameters that are difficult to determine.

The influence of methylammonium iodide concentration on the properties of perovskite solar cells

AbstractThis study focuses on improving the quality of MAPbI3‐based perovskite films by adjusting the concentration ratios of the methylammonium iodide (MAI) precursor using a two‐step sequential deposition method. The primary objective is to explore how altering the MAI concentration influences the microstrain, dislocation density, perovskite film quality, and their subsequent impact on the performance of perovskite solar cells. The examined device configuration CdS/MAPbI3/Spiro‐OMeTAD demonstrates impressive power conversion efficiency of 12.05%, Voc of 1.02 V, Jsc of 16.2 mA cm−2, and fill factor of 0.73. X‐ray diffraction and scanning electron microscope analyses show improved crystal quality and surface characteristics with reduced microstrain, dislocation density, larger crystal grains, and minimized pinholes. The investigation of MAPbI3's optical and electrical characteristics provides in‐depth insights, facilitating the optimization of MAI precursor concentrations for improved perovskite film development and enhanced solar cell performance.

Dopant-additive synergism enhances perovskite solar modules

Perovskite solar cells (PSCs) are among the most promising photovoltaic technologies owing to their exceptional optoelectronic properties1,2. However, the lower efficiency, poor stability and reproducibility issues of large-area PSCs compared with laboratory-scale PSCs are notable drawbacks that hinder their commercialization3. Here we report a synergistic dopant-additive combination strategy using methylammonium chloride (MACl) as the dopant and a Lewis-basic ionic-liquid additive, 1,3-bis(cyanomethyl)imidazolium chloride ([Bcmim]Cl). This strategy effectively inhibits the degradation of the perovskite precursor solution (PPS), suppresses the aggregation of MACl and results in phase-homogeneous and stable perovskite films with high crystallinity and fewer defects. This approach enabled the fabrication of perovskite solar modules (PSMs) that achieved a certified efficiency of 23.30% and ultimately stabilized at 22.97% over a 27.22-cm2 aperture area, marking the highest certified PSM performance. Furthermore, the PSMs showed long-term operational stability, maintaining 94.66% of the initial efficiency after 1,000 h under continuous one-sun illumination at room temperature. The interaction between [Bcmim]Cl and MACl was extensively studied to unravel the mechanism leading to an enhancement of device properties. Our approach holds substantial promise for bridging the benchtop-to-rooftop gap and advancing the production and commercialization of large-area perovskite photovoltaics.

Manipulation of Crystal Orientation and Phase Distribution of Quasi-2D Perovskite through Synergistic Effect of Additive Doping and Spacer Engineering.

The diammonium precursor 1,4-phenylenedimethanammonium (PDMA) was used as a large organic spacer for the preparation of Dion-Jacobson-type quasi-2D perovskites (PDMA)(MA)n-1PbnI3n+1 (MA = methylammonium). Films with composition ⟨n⟩ = 5 comprised randomly orientated grains and multiple microstructural domains with locally differing n values. However, by mixing the Dion-Jacobson-type spacer PDMA and the Ruddlesden-Popper-type spacer propylammonium (PA), the crystal orientation in both the vertical and the horizonal directions became regulated. High crystallinity owing to well-matched interlayer distances was observed. Combining this spacer-engineering approach with the addition of methylammonium chloride (MACl) led to full vertical alignment of the crystal orientation. Moreover, the microstructural domains at the substrate interface changed from low-n (n = 1, 2, 3) to high-n (n = 4, 5), which may be beneficial for hole extraction at the interface between perovskite and hole transport layer due to a more finely tuned band alignment. Our work sheds light on manipulating the crystallization behavior of quasi-2D perovskite and further paves the way for highly stable and efficient perovskite devices.

In Situ Probing the Crystallization Kinetics in Gas‐Quenching‐Assisted Coating of Perovskite Films

AbstractThe pursuit of commercializing perovskite photovoltaics is driving the development of various scalable perovskite crystallization techniques. Among them, gas quenching is a promising crystallization approach for high‐throughput deposition of perovskite films. However, the perovskite films prepared by gas‐quenching assisted blade coating are susceptible to the formation of pinholes and frequently show inferior crystallinity if the interplay between film coating, film drying, and crystallization kinetics is not fully optimized. That arguably requires a thorough understanding of how single processing steps influence the crystallization kinetics of printed perovskite films. Here, in situ optical spectroscopies are integrated into a doctor‐blading setup that allows to real‐time monitor film formation during the gas‐quenching process. It is found that the essential role of gas quenching treatment is in achieving a smooth and compact perovskite film by controlling the nucleation rate. Moreover, with the assistance of phase‐field simulations, the role of excessive methylammonium iodide is revealed to increase grain size by accelerating the crystal growth rate. These results show a tailored control of crystal growth rate is critical to achieving optimal film quality, leading to fully printed solar cells with a champion power conversion efficiency of 19.50% and mini solar modules with 15.28% efficiency are achieved.

Highly conductive flat grains of cesium lead bromide perovskites via additive engineering with methylammonium bromide

Methylammonium bromide yields highly conductive flat grains of cesium lead bromide perovskites.

Benign methylformamidinium byproduct induced by cation heterogeneity inhibits local formation of δ-phase perovskites

Methylammonium chloride (MACl) selectively promotes the formation of N-methylformamidinium (MFA+)PbI3 at grain boundaries (GBs) and as clusters near GBs while suppress the formation of δ-FAPbI3.

Unveiled effects of the methylammonium chloride additive on formamidinium lead halide: expediting carrier injection from the photoabsorber to carrier transport layers through spontaneously modulated heterointerfaces in perovskite solar cells

Time-resolved spectroscopies unveil the additional effects of the widely used methylammonium chloride (MACl) additive on FAPbI3 photoabsorber in perovskite solar cells, spontaneously modulating heterointerfaces for accelerating carrier injections.

An efficient method for extracting pure DNA from the oil seed crop Sesamum indicum L.

Sesame (Sesamum indicum L.) is a vital oil seed crop highly rich in sesamin, sesamolin, and tocopherols, which are some of its nutrient and antioxidant components. Sesame is rich in genetic resources with vast germplasm, tolerance to various biotic and abiotic stresses, and quality-related traits. Therefore, a comprehensive study on searching important genes/quantitative trait loci (QTLs) is needed to get better oil from the plant. Pure DNA is the prerequisite to perform various molecular-level functions, including gene amplification, genomewide association studies, and other molecular breeding applications used in crop improvement. However, it also has high polysaccharides and secondary metabolites that interfere with DNA extraction, and precise quantification of DNA is essential for DNA-related biological functions. Several DNA extraction methods, such as cetyl-tetra methyl ammonium bromide (CTAB), sodium dodecyl sulphate (SDS), and commercially available kits, are present and used in molecular biology applications. Due to the complexity and interference of polysaccharides and polyphenols, the available methods required numerous modifications in the protocol to get pure and intact DNA. This study illustrates several modifications to get the pure DNA using the CTAB-based method with the additional step of adding a high salt concentration, which results in a better quantity and quality of DNA extracted from sesame leaves and root tissue. The lysis buffer and cold storage to efficiently eliminate the polysaccharide components were found to be limiting factors affecting DNA yield; therefore, buffer composition, along with storage duration, was modified in the present study. This method worked well to get good quality and quantity of DNA and will help researchers conduct next-generation sequencing and other genetic investigations directly associated with high-quality DNA in the oilseed crop.