Phenyltrimethylammonium Chloride Research Articles

Phenyltrimethylammonium chloride additive for highly efficient and stable FAPbI3 perovskite solar cells

Formamidinium lead triiodide (FAPbI3)-rich perovskite absorbers have emerged as the frontrunners for the development of perovskite solar cells (PSCs), but pristine FAPbI3 absorber exhibits phase instability because of external stressors during device manufacture and operation. In this work, we systematically study the function of a trace amount of phenyltrimethylammonium chloride (PTAC) additive in FAPbI3-based perovskites. The introduced PTAC have a strong electrostatic interaction with perovskite because of the coordination of electron-rich benzene ring unit and under-coordinated Pb2+, which leads to the decrease of the trap density and the release of the lattice strain. Simultaneously, the increased work function of modulated film optimizes the band alignment, promoting carrier transport and reducing nonradiative recombination, thereby improving the open-circuit voltages and fill factors. Consequently, the modulated PSCs achieve a champion power conversion efficiency of 24.51%, and exhibit much better stability by retaining 90% of their initial efficiency after 1000 hours constant illumination under maximum power point tracking measurement.

Controlled crystallization and surface engineering of mixed-halide γ-CsPbI2Br inorganic perovskites via guanidinium iodide additive in air-processed perovskite solar cells

In this report, we demonstrate enlarged grain size (up to ∼3 μm) in ambient-stable black γ-phase CsPbI2Br thin films through the regulated addition of guanidinium iodide (GAI) as an effective volatile additive. Nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) measurements indicate the complete sublimation of GAI following annealing, with no inclusion inside the final γ-CsPbI2Br perovskite lattice. GAI is found to participate by retarding the cation–anion reaction via the Cs+ and GA+ cation-exchange process. We find that inorganic perovskite solar cells (IPSCs) devices made from (CsPbI2Br)0.925 + 0.075 GAI and a phenyltrimethylammonium chloride (PTACl) passivation retain a solar-friendly band-gap of 1.91 eV and excellent device performance, with the best open-circuit voltage reaching as high as 1.34 V, with highly reproducible and stable photo conversion efficiencies of 16.88% (for 0.09 cm2) and 15.60% (large area 1 cm2) under ambient conditions. Photostability analysis further demonstrated negligible efficiency loss over 1000 h under continuous one-sun equivalent illumination, indicating GAI additive as a promising approach toward ambient stable, all-inorganic high-efficiency solar cells.

Adsorption behaviour of clomazone on inorganic and organically modified natural montmorillonite from Bogovina (Serbia)

AbstractThe adsorption behaviour of the herbicide clomazone on inorganic and organically modified montmorillonite from the Bogovina deposit in Serbia was investigated. Montmorillonite was modified first with NaCl and then with organic complexes such as hexadecyltrimethylammonium bromide (HDTMA) and phenyltrimethylammonium chloride (PTMA). Changes in the surface properties and morphology of the montmorillonite before and after the modification with various concentrations of organic complexes were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). Adsorption of clomazone on all examined samples was investigated using the batch adsorption method. Montmorillonite modified with HDTMA-bromide displayed greater uptake of the clomazone compared to the PTMA-montmorillonite, and both organically modified montmorillonites displayed greater uptake of the herbicide compared to the inorganic montmorillonite. Comparing the Freundlich coefficient and maximum adsorbed clomazone quantity values obtained by Langmuir model, the levels of adsorption of clomazone decreased in the following order: HDTMA-montmorillonite with 1.00 cation-exchange capacity (CEC) saturation > HDTMA-montmorillonite with 0.75 CEC saturation > PTMA-montmorillonite with 1.00 CEC saturation > PTMA-montmorillonite with 0.75 CEC saturation > HDTMA-montmorillonite with 0.50 CEC saturation > HDTMA-montmorillonite with 0.25 CEC saturation > PTMA-montmorillonite with 0.50 CEC saturation > PTMA-montmorillonite with 0.25 CEC saturation > Na-montmorillonite > raw sample. The type and content of an organic cation plays an important role in the behaviour of clomazone in a solid/liquid system. It is concluded that organically modified montmorillonite from Bogovina might be used as an effective adsorbent for clomazone.

The Role of Dimethylammonium Iodide in CsPbI3 Perovskite Fabrication: Additive or Dopant?

AbstractThe controllable growth of CsPbI3 perovskite thin films with desired crystal phase and morphology is crucial for the development of high efficiency inorganic perovskite solar cells (PSCs). The role of dimethylammonium iodide (DMAI) used in CsPbI3 perovskite fabrication was carefully investigated. We demonstrated that the DMAI is an effective volatile additive to manipulate the crystallization process of CsPbI3 inorganic perovskite films with different crystal phases and morphologies. The thermogravimetric analysis results indicated that the sublimation of DMAI is sensitive to moisture, and a proper atmosphere is helpful for the DMAI removal. The time‐of‐flight secondary ion mass spectrometry and nuclear magnetic resonance results confirmed that the DMAI additive would not alloy into the crystal lattice of CsPbI3 perovskite. Moreover, the DMAI residues in CsPbI3 perovskite can deteriorate the photovoltaic performance and stability. Finally, the PSCs based on phenyltrimethylammonium chloride passivated CsPbI3 inorganic perovskite achieved a record champion efficiency up to 19.03 %.

The Role of Dimethylammonium Iodide in CsPbI3 Perovskite Fabrication: Additive or Dopant?

The controllable growth of CsPbI3 perovskite thin films with desired crystal phase and morphology is crucial for the development of high efficiency inorganic perovskite solar cells (PSCs). The role of dimethylammonium iodide (DMAI) used in CsPbI3 perovskite fabrication was carefully investigated. We demonstrated that the DMAI is an effective volatile additive to manipulate the crystallization process of CsPbI3 inorganic perovskite films with different crystal phases and morphologies. The thermogravimetric analysis results indicated that the sublimation of DMAI is sensitive to moisture, and a proper atmosphere is helpful for the DMAI removal. The time-of-flight secondary ion mass spectrometry and nuclear magnetic resonance results confirmed that the DMAI additive would not alloy into the crystal lattice of CsPbI3 perovskite. Moreover, the DMAI residues in CsPbI3 perovskite can deteriorate the photovoltaic performance and stability. Finally, the PSCs based on phenyltrimethylammonium chloride passivated CsPbI3 inorganic perovskite achieved a record champion efficiency up to 19.03 %.

Examination of the influence of phenyltrimethylammonium chloride (PTMA) concentration on acetochlor adsorption by modified montmorillonite

ABSTRACTThe results presented in this paper show an impact of the concentration of the aromatic organic cation on the adsorption of acetochlor on the surface of the organic-modified montmorillonite. Natural montmorillonite from Bogovina (Boljevac municipality, Serbia) was used for organic modification in this experiment. Cation exchange capacity of this montmorillonite (86 mmol 100 g−1 of clay) was determined using the methylene blue method. In pretreatment, montmorillonite was modified with NaCl. For the purpose of organic modification, three different concentrations of phenyltrimethylammonium chloride (PTMA) have been selected, based on calculated CEC value: 43 mmol 100 g−1 of clay (0.5 CEC), 86 mmol 100 g−1 of clay (1 CEC) and 129 mmol 100 g−1 of clay (1.5 CEC). The changes in the properties of the inorganic and organic modified montmorillonite were examined using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and batch equilibrium method. Freundlich coefficients show higher uptake of the herbicide by montmorillonite modified with PTMA, compared to inorganic-modified montmorillonite. The results also indicate the influence of the organic cation concentration on the adsorption of the selected herbicide.

Enhanced emulsifying properties of wood-based cellulose nanocrystals as Pickering emulsion stabilizer

Cellulose nanocrystals are hydrophilic nanomaterials, which limits their applications as interfacial compounds. Herein, we propose using modified wood-based cellulose nanocrystals as Pickering emulsion stabilizer. Wood cellulose was consecutively oxidized and modified with phenyltrimethylammonium chloride to create hydrophobic domains comprised of phenyl groups. These modified oxidized cellulose nanocrystals (m-O-CNCs) were homogeneous/electrostatically stable in water and they can stabilize O/W Pickering emulsions. The dispersed phase volume fraction (DPVF) of the Pickering emulsion was 0.7 at around 1.5g/L, whereas the tween-20 control needed a 13-fold greater concentration to have a similar DPVR. In addition, these m-O-CNC stabilized Pickering emulsions also showed good mechanical and thermal stability against centrifugation and heat, as well as size controllability. In terms of stability, size controllability, surfactant-free status, these m-O-CNCs possess superior and enhanced emulsifying properties. Future research for these new interfacial materials have potential in applications, for personal care, cosmetic and pharmaceutic industries.

Chemical Surface, Thermal and Electrical Characterization of Nafion Membranes Doped with IL-Cations

Surface and bulk changes in a Nafion membrane as a result of IL-cation doping (1-butyl-3-methylimidazolium tetrafluoroborate or BMIM+BF4 and phenyltrimethylammonium chloride or TMPA+Cl−) were studied by X-ray photoelectron spectroscopy (XPS), contact angle, differential scanning calorimetry (DSC) and impedance spectroscopy (IS) measurements performed with dry samples after 24 h in contact with the IL-cations BMIM+ and TMPA+. IL-cations were selected due to their similar molecular weight and molar volume but different shape, which could facilitate/obstruct the cation incorporation in the Nafion membrane structure by proton/cation exchange mechanism. The surface coverage of the Nafion membrane by the IL-cations was confirmed by XPS analysis and contact angle, while the results obtained by the other two techniques (DSC and IS) seem to indicate differences in thermal and electrical behaviour depending on the doping-cation, being less resistive the Nafion/BMIM+ membrane. For that reason, determination of the ion transport number was obtained for this membrane by measuring the membrane or concentration potential with the samples in contact with HCl solutions at different concentrations. The comparison of these results with those obtained for the original Nafion membrane provides information on the effect of IL-cation BMIM+ on the transport of H+ across wet Nafion/BMIM+ doped membranes.

Complexation Reaction Using Ammonium Based Chloride Compounds for Preparation of Eutectic Mixtures

In this study, we are interested in the eutectic processing of chloride compounds, and decided to focus on ammonium based compounds that can provide sufficient insight in the fundamental chemistry. 14 types ammonium based chloride compounds namely ammonium chloride, methanaminium chloride, dimethylammonium chloride, trimethylammonium chloride, tetramethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, carboxytrimethylmethanaminium chloride, phenyltrimethylammonium chloride, benzyltrimethylammonium chloride, (vinylbenzyl)trimethylammonium chloride, 2-acetoxytrimethylethanaminium chloride, (2-acetoxypropyl)trimethylammonium chloride and 2-(benzoyloxy)trimethylethanaminium chloride were used in this study. This research led to a hypothesis that the ammonium based chloride compounds could be react with the urea by complexing the hydrogen groups that are hydrogen bond donor giving eutectic mixtures. However, functional groups have plays an important role to influence thermal properties of those eutectic mixtures. This is regarded to be a motivating finding that will be important to most future research work involving complexation reaction for the production of eutectic mixtures.

One-pot three-component synthesis of α-amino phosphonate derivatives

Abstract A new and highly flexible procedure is described for the synthesis of α-amino-, α-hydrazino-, and α-N-hydroxyamino Phosphonates by reaction between trimethylphosphite and in situ generated imines (iminium salts, oximes, hydrazones, nitrones) by using phenyltrimethylammonium chloride as catalyst (1 mol%) in reagent grade dichloromethane at 40 °C.

Organoclay Formulations of Acetochlor: Effect of High Salt Concentration

This study aimed to evaluate new methodology for designing ecologically acceptable formulations of acetochlor. Modification of montmorillonite with phenyltrimethylammonium chloride (PTMA) or benzyltrimethylammonium chloride (BTMA) and organoclay formulations of acetochlor were prepared in the presence of high concentrations of sodium chloride (150 g/L). Acetochlor concentration in the equilibrium solutions was determined by HPLC. Release of acetochlor in a water system was performed by a funnel experiment. Leaching of acetochlor in soil was determined by a bioassay using a column technique and Setaria viridis as a test plant. The adsorbed amounts of acetochlor on montmorillonite exchanged by PTMA or BTMA were increased as NaCl concentration increased in the equilibrium solution. Leaching of acetochlor from organoclay formulations was significantly inhibited to the top soil layer (0-5 cm) when the formulations were prepared at extreme NaCl concentration (100-150 g/L). These results are in accord with a funnel experiment that showed a reduction in acetochlor release from the montmorillonite-based formulations. The application of this method for herbicide formulation would produce ecologically acceptable herbicide formulations that can significantly minimize the risk to groundwater pollution.

Inhibition of the corrosion of low carbon steel in acidic solution by selected quaternary ammonium compounds

Potentiodynamic polarisation studies were carried out on the inhibition of low carbon steel in 0.1M hydrochloric acid solution over the temperature range 20‐60°C at different inhibitor concentrations by various quaternary ammonium salts and cationic surfactants. The inhibitors examined were tetraethyl ammonium chloride, tetrabutyl ammonium chloride, benzyltrimethyl ammonium chloride, benzyltriethyl ammonium chloride, benzyltributyl ammonium chloride, phenyltrimethyl ammonium chloride, alkylbenzyldimethyl ammonium chloride, tetradecyltrimethyl ammonium bromide and cetyltrimethyl ammonium bromide. Maximum inhibition efficiencies of cationic surfactants were observed around and above critical micelle concentration (cmc), while the inhibition efficiencies of the quaternary ammonium salts were found to increase with the increase in their concentrations. The degree of shift in Ecorr value, together with change in anodic and cathodic Tafel slopes (ba, bc), revealed that cationic surfactants behave as an anodic inhibitor, while quaternary ammonium salts behave as mixed type inhibitors. Inhibition efficiencies of studied inhibitors seem to be closely related with the chain length of the alkyl group as well as the presence of benzene ring in quaternary ammonium compounds. Thermodynamic and kinetic parameters for dissolution and adsorption were also calculated.

Nylon 66, Nylon 46, and Pet Phase-Transfer-Catalyzed Alkaline Depolymerization at Atmospheric Pressure

The depolymerization of PET, nylon 66, and nylon 46 at high temperatures in an autoclave is well known in the patent literature. We sought to invent processes for the depolymerization of PET, nylon 66, and nylon 46 in alkaline solutions at low temperatures and atmospheric pressure. A method was developed for the depolymerization of polyethylene terephthalate (PET) which involved the use of quarternary ammonium salt phase-transfer catalysts in saponification processes at atmospheric pressure and temperatures as low as room temperature. Phenyltrimethylammonium chloride, hexadecyltrimethylammonium bromide, trioctylmethylammonium chloride, and trioctylmethylammonium bromide were found to be effective catalysts for the depolymerization of PET in 5% aqueous sodium hydroxide solutions at temperatures as high as 80°C and atmospheric pressure to form terephthalic acid in yields as high as 93%. The catalyst could be recycled. The alkaline phase-transfer-catalysis approach was then successfully applied for the depolymerizations of nylon 66 and nylon 46. Benzyltrimethylammonium bromide was discovered to be an effective phase-transfer catalyst in 50 wt.% sodium hydroxide solution for the conversion of nylon 46 to oligomers. The collected nylon 46 oligomers were repolymerized using solid-state polymerization techniques to form high-molecular-weight nylon 46. Nylon 66 fibers were depolymerized in the presence of benzyltrimethylammonium bromide in 50% sodium hydroxide to form oligomers and a monomer. Adipic acid was isolated.

O-Methylation with Phenyltrimethylammonium chloride.

O-Methylation with Phenyltrimethylammonium chloride.

Micellar electrokinetic chromatography—mass spectrometry using a high-molecular-mass surfactant on-line coupling with an electrospray ionization interface

On-line coupling between micellar electrokinetic chromatography (MEKC) and mass spectrometry (MS) was studied with a high-molecular-mass surfactant and an electrospray ionization interface (ESI). A high-molecular-mass surfactant, butyl acrylate-butyl methacrylate-methacrylic acid copolymer sodium salt (BBMA), was employed as a pseudo-stationary phase for an on-line MEKC-MS system. BBMA and a minor component separated by size-exclusion chromatography were determined by ESI-MS. No major ion from the BBMA polymer was detected. The BBMA micelle functioned successfully as the pseudo-stationary phase in a 10 m M ammonium formate buffer containing 10% methanol. Five standard compounds, phenyltrimethylammonium chloride, 1-naphthylamine, quinine sulfate, tetraphenylphosphonium chloride and octaoxyethylenedodecanol, were separated by MEKC and detected by MS. The effects of the concentrations of BBMA on the separation and sensitivity in MEKC-MS were studied. MEKC-MS with BBMA was applied to the separation and detection of a standard mixture of sulfamides.

Extension growth and cold hardening of young ?Valencia? orange trees sprayed with AMO-1618

Rate of extension growth, as measured by height, of 2-month-old ‘Valencia’ orange trees (Citrus sinensis (L.) Osbeck) on rough lemon rootstock (C. limon Burm. f.) was reduced to 0.5 mm from 5.0 mm day−1 with 0.1% (w/v) sprays of the growth retardant AMO-1618 (4 hydroxy-5-isopropyl-2-methyl phenyl trimethyl-ammonium chloride, 1 piperdine carboxylate) every 2 weeks during 11 weeks under natural daylight in a glasshouse. Trees sprayed with AMO-1618 were 10-fold shorter, more compact in appearance, and leaves were greener and more oval shaped than those on untreated trees. There was no ‘chemical burn’. AMO-1618-sprayed trees were more cold hardy than untreated trees during controlled-temperature, cold-hardening regimes. Alone, AMO-1618 had no effect on freeze tolerance at -5.5° C. AMO-1618 also was associated with greater tree tolerance to freeze injury determined by O2 uptake in ‘Valencia’ leaves to as low as -6.7° C.

Effect of Some Cationic Detergents on Macromolecularly Stabilised Emulsions with Special Reference to Sodium Alginate and Gum Arabic as Emulsifiers

Abstract The effect of some cationic detergents viz. cetyl pyridinium bromide, lauryl pyridinium chloride and phenyl trimethyl ammonium chloride has been studied on stabilised by sodium alginate and gum arabic emulsions. Zeta potentials were measured at different concentrations of cationic detergents microelectrophoretically. The particle size was determined microphotographically. With the help of zeta potential and particle size the interaction energies were calculated by summing up attraction and repulsion energies in the light of D.V.O. theory. For attraction energy the van der Waals constant was computed theoretically from the optical data and was obtained to be 6.7×10−14 erg. The interaction energies thus obtained gave very high energy barriers which completely obviated the occurrence of flocculation in primary minima, causing flocculation to occur in secondary minima. The theoretical degrees of aggregation were calculated and plotted at different values of A. The flocculation occurring in the system was observed haemocytometrically by counting the number of singlets and doublets and the degrees of aggregation were calculated. With the help of observed degrees of aggregation the operating value of van der Waals constant has been estimated by interpolating them into the theoretical curves, which is an indirect approach to ascertain the value of van der Waals constant. The values of A obtained are 3.0×10−13 and 2.6×10−13 erg for sodium alginate and gum arabic systems respectively. The binding parameters, number of binding sites available and free energy of adsorption have also been calculated.

Effect of some cationic detergents on the macromolecular stabilised emulsion with special reference to pepsin as emulsifier

The effect of some cationic detergents viz Phenyl Trimethyl Ammonium Chloride, Lauryl pyridinium chloride, Cetyl pyridinium Bromide and Aerosol C-61, on the nujol/water emulsion stabilised by pepsin, has been studied. The detergents were added in two ways: 1. before emulsification; 2. after emulsification. The results were compared by their flocculation concentrations obtained at zero point of charge. From these values it is observed that the flocculation concentrations before emulsification are higher than those obtained after emulsification. The stability of the present system is discussed in the light of DVO theory. The high potential energy barriers obtained obviated the possibility of flocculation in primary minima. Therefore, to explain the results, the flocculation was assumed to occur in the secondary minima. The flocculation studies were carried out haemocytometrically which enabled to calculate the degrees of aggregation (D). In order to account for the observed values of D, the effective van der Waals constant of the system should be 1.0×10−12 erg. The binding parameters and free energies have also been calculated.

Effect of Cationic Detergents on the Lecithin Stabilized O/W Emulsion

Abstract An oil-in-water system (Nujol being the oil phase) stabilized by the phospholipid, lecithin, has been chosen in this study. The system being negatively charged initially, cationic detergents like lauryl pyridinium chloride (LPC), Cetyl pyridinium bromide (CPB), Phenyl trimethyl ammonium chloride (Ammonyx-200) and Cetyl dimethyl benzyl ammonium chloride (CDBAC) have been employed in order to study their influence on the flocculation and coalescence rates and the degree of aggregation haemocytometrically. Zeta potentials (ξ) have been determined at the corresponding concentrations of the detergents by microcataphoresis and with these values the potential energies and then ultimately the operating van der Waals constant of the system has been determined. From the log C-ξ values it is evident that except Ammonyx-200 which is not an effective cationic detergent, all the others have reversed the charge of the system and their efficiencies are in the order CDBAC>CPB>LPC. The different binding parameters, number of binding sites available for adsorption and free energy of the surface have also been calculated.

P-(3-hydroxy-3-phenyltriazeno)-phenyltrimethyl-ammonium chloride as a new colour reagent for certain metal ions

The synthesis and qualitative reactions of p-(3-hydroxy-3-phenyltriazeno)phenyltrimethyl-ammonium chloride are described. The solubilising effect of the quarternary ammonium group is studied; this group is valuable for the conversion of organic precipitants to colorimetric reagents.