Ammonium Iodide Research Articles

The novel extraordinary separation and preconcentration approach for Cd2+: “Hydrophobic Immiscible Chelating Fluid” based micro-extraction

The novel, extraordinary and highly selective separation and preconcentration approach based on hydrophobic immiscible chelating fluid (HICF) having superior features (simultaneous chelation, extraction and masking) and combined with automatized syringe discharge system by peristaltic pump was established firstly for simultaneous chelation and micro-extraction of Cd2+. Mixture of tetra butyl ammonium iodide, tetra butyl ammonium fluoride, n-pentanol (1:1:10) and dithizone were used to formulate HICF. The parameters including pH, chelator concentration on both characteristic of HICF and extraction of Cd2+, time of vortex mixing, amount of HICF and sample volume were optimized and investigated in detail. The optimized method has permitted to obtain 25 preconcentration factor (PF) and detect the lowest cadmium concentration having 2.1 µg L−1 (LOD) in the aqueous solution. Interference effect of defiant metal cations was investigated in detail. The dynamic range of the method (LDR) was obtained linearly between 7.2 and 1500 µg L−1. Relative standard deviations (% RSD) were below than % 4.2 throughout the experiments. The envisaged possible extraction mechanisms were explained. The proposed novel method was validated with applications of multiple analyte-addition recovery tests in water samples (tap, lake and natural spring water) and analysis of standard reference material (UME EnvCRM 03 Elements in Soil). Quantitative satisfactory recovery values changing between 98 and 106 % were obtained. Validated method was also applied to determine Cd contents of sediment, mushroom and raw tobacco samples. The main advantage of HICF is that it contains masking and chelating agents and extraction solvent in only one liquid. Therefore, possible concentration and volume errors were minimized by single micropipette injection that ensured time saving and simplicity for applicability of the method by the analysts. Moreover, automated syringe discharge system has provided repeatable and precision extraction results.

High‐Performance Perovskite Solar Cells with Low Open‐Circuit Voltage Loss and Excellent Stability after p‐F‐PEAI Posttreatment

Photoelectric properties of perovskite solar cells (PSCs) are closely linked to defects on the surface of perovskite in the preparation process, which have a significant impact on the open‐circuit voltage (VOC) of devices. It is necessary for high‐performance PSCs to suppress the non‐radiative recombination at the interface and improve the charge transfer. Herein, phenylethyl ammonium iodide containing fluorine (p‐F‐PEAI) is utilized to treat the perovskite film, which can optimize the energy‐level alignment between perovskite layer and hole‐transport layer to promote charge transfer and reduce non‐radiative recombination by passivating interface defects and inhibiting the generation of Pb0. The introduction of fluoride can enhance the electropositivity of −NH3+ to obtain excellent passivation and moisture resistance. The p‐F‐PEAI‐modified PSCs achieve a superior power conversion efficiency of 22.56% with remarkable VOC (1.20 V) and maintain 96% of the initial optimal value after 1000 h without encapsulation.

Synthesis, Characterization and Disinfection Efficiency Evaluation of Quaternary Ammonium Iodide Derivatives of Gum Arabic

Synthesis, Characterization and Disinfection Efficiency Evaluation of Quaternary Ammonium Iodide Derivatives of Gum Arabic

Stable high conversion efficiency of Quasi-2D perovskite solar cells via potassium iodide as additive

Although two-dimensional (2D) perovskite is more stable than three-dimensional (3D) perovskite, its poor film quality and low photoelectric conversion efficiency are still the focuses of researchers. In this article, we introduce a simple and effective method to modify the quasi-2D (BA)2(MA)3Pb4I13 perovskite solar cells by introducing potassium iodide as an additive. We found that the introducing K ion made perovskite film more compact, reduced the number of grain boundaries and regulated the band alignment. Besides, the incorporation of K+ reduced the nonradiative recombination and hysteresis effect of the device. As a result, the power conversion efficiency (PCE) of solar cells increased from initial 13.91% to 16.82% under optimized concentration of 16% (mole ratio compared to N-butyl ammonium iodide BAI). What is more, the device with K+ modification showed excellent environmental stability, which could maintain 95% of their original efficiency after 720 h under ambient air condition, whereas the pristine devices without K+ only keep 53% of their initial efficiency and the thermal stability has also been improved. This result provides a simple and promising method through additive engineering to achieve high PCE and stable quasi-2D perovskite solar cells.

Tuning N/O-doped carbon materials for supercapacitors by direct pyrolysis of imidazolinium polymer

Using structurally adjustable polymer to develop pseudocapacitive carbon materials with rich faradaic-active functionalities in the readily accessible skeleton for supercapacitors is important and still challenging. In this paper, using the “aromatic aldehydes ammonia condensation” idea and starting from the terephthalaldehyde and ammonium, highly pseudocapacitive active porous carbon materials were fabricated by simple “one pot method” and pyrolysis. The iodine-modified imidazolinium network polymer synthesized carbon at 700 °C (INP-I-700) shows a high specific surface area (606 m2 g−1) and pore volume of 0.30 cm3 g−1. Thanks to the hierarchically microporous, mesoporous and macroporous structure and diverse pseudocapacitive active N,O species, the ammonium iodide synthesized imidazolinium polymer derived INP-I-700 porous carbon material demonstrates a high specific capacitance of 199.1 F g−1 at 1 A g−1, along with superior cycling stability for symmetric supercapacitor configure with 99 % capacity retention after 10,000 cycles in 1 M Na2SO4 aqueous electrolyte. Furthermore, an attractive energy density of 27.7 Wh/kg at power density of 496.5 W/kg in Na2SO4 electrolyte in the voltage range of 0–2.0 V for the assembled symmetric system can be reached. The outcome of this paper can provide guidance for the construction of functionalized carbon-based materials with large specific surface area.

Improved perovskite triboelectric nanogenerators by effective defect passivation and interface modulation

Perovskite-based triboelectric nanogenerators (TENGs) have obtained wide attention and investigation due to their excellent dielectric and electrical properties, as well as the diversity of perovskite materials. In this work, phenethyl ammonium iodide (PEAI) was applied to tailor the interface of MAPbI3 films, to form a 2D/3D heterojunction, and to passivate defects of films. The TENGs after PEAI passivation achieved significant improvement in voltage and current density with an increase in the output voltage from 33.3 to 40.1 V, and the current density was improved from 9.1 to 10.1 mA/m2. The improved output properties might be attributed to changes in the triboelectric charge density, carrier mobility, reduced interfacial combination by effective defect passivation, and favorable charge transporting by constructing 2D/3D heterojunctions for the effect of the built-in electric field. This work demonstrates that interfacial modification is one of the feasible methods for improving the performance of TENGs and supplies further possibilities for high-performance perovskite-based TENGs.

Four-Component Synthesis of 9H-Pyrimido[4,5-b]indoles Using Ammonium Iodide as the Nitrogen Source

A four-component synthesis of 2-phenyl-9H-pyrimido[4,5-b]indoles was developed using indole-3-carboxaldehydes, aromatic aldehyde and ammonium iodide as the raw materials under transition-metal-free conditions. The pyrimidine ring was formed in one pot through [4 + 2] annulation reaction. Four C–N bonds were formed in one pot promoted by iodine and iodide additives. This work is highlighted by using two ammonium iodides as the sole nitrogen source.

A General Strategy to Remove Metal Aggregates toward Metal-Nitrogen-Carbon Catalysts with Exclusive Atomic Dispersion.

Metal- and nitrogen-doped nanocarbons (M-N-Cs) are promising alternatives to precious metals for catalyzing electrochemical energy conversion processes. However, M-N-Cs synthesized by high-temperature pyrolysis frequently suffer from compositional heterogeneity with the simultaneous presence of atomically dispersed M-Nx sites and crystalline metal nanoparticles (NPs), which hinders the identification of active sites and rational optimization in performance. Herein, a universal and efficient strategy is reported to obtain both precious- and nonprecious-metal-based M-N-Cs (M = Pt, Fe, Co, Ni, Mn, Cu, Zn) with exclusive atomic dispersion by making use of ammonium iodide as the etchant to remove excessive metal aggregates at high temperature. Taking Pt-N-C as a proof-of-concept demonstration, the complete removal of Pt NPs in Pt-N-C enables clarification on the contributions of the atomic Pt-Nx moieties and Pt NPs to the catalytic activity toward the hydrogen evolution reaction. Combined electrochemical measurements and theoretical calculations identify that the atomic Pt-Nx moieties by themselves possess negligible activity, but they can significantly boost the activity of the Pt NPs via the synergistic effect.

Machine learning assisted investigation of the barocaloric performance in ammonium iodide

Using the ab initio-based training database, we trained the potential function for ammonium iodide (NH4I) based on a deep neural network-based model. On the basis of this potential function, we simulated the temperature-driven β ⇒ α-phase transition of NH4I with isobaric isothermal ensemble via molecular dynamics simulations, the results of which are in good agreement with recent experimental results. As it increases near the phase transition temperature, a quarter of ionic bonds of NH4+-I− break so that NH4+ starts to rotate randomly in a disorderly manner, being able to store thermal energy without a temperature rise. It is found that NH4I possesses a giant isothermal entropy change (∼93 J K−1 kg−1) and adiabatic temperature (∼27 K) at low driving pressure (∼10 MPa). In addition, through partial substitution of I by Br in NH4I, it is found that the thermal conductivity can be remarkably improved, ascribed to the enhancement of lifetime of low frequency phonons contributed by bromine and iodine. The present work provides a method and important guidance for the future exploration and design of barocaloric material for practical applications.

DBUHI3 complex an efficient catalyst for the synthesis of 2-phenyl benzimidazole and benzothiazole derivatives

Herein, we have reported the facile synthesis of various benzimidazole/ benzothiazole by using DBU?iodine?iodide as a green and simple catalyst. The R3NHI3 complexes have been formed by reacting an aqueous mixture of ammonium iodide and molecular iodine with the aqueous solution of amine. The structure of R3NHI3 complexes has been confirmed by spectroscopic techniques. The prepared amine?iodine complexes were screened as a catalysts in the synthesis of benzimidazole/benzothiazoles. Among the screened catalysts DBUHI3 complex has been found as most efficient catalyst. The synthesis of benzimidazoles and benzothiazoles has been achieved with the reaction of ophenylene diamine/o-aminothiophenol and various substituted aryl aldehyde using DBUHI3 as a catalyst. The present protocol has offered some advantages over other reported protocols such as the mild reaction condition, commercially available precursors, inexpensive catalyst, short reaction time, the broad scope of the substrate, high yield, simple isolation of the product and environmentally benign method.

Organic ammonium iodide salts as passivation for buried interface enables efficient and stable NiOx based p-i-n perovskite solar cells

The interfaces between a halide perovskite absorber film and its charge transporting layers have been identified as one of the key bottlenecks for achieving high performance and stability.

Iodine(III)‐Mediated Free‐Aniline Iodination through Acetyl Hypoiodite Formation: Study of the Reaction Pathway

AbstractThe first iodine(III)‐mediatedpara‐selective iodination protocol for free anilines as well as the mechanistic elucidation of the reaction pathway is described. The developed method proceeded under clean, non‐toxic, efficient, and in general mild reaction conditions. To the best of our knowledge this report describes for the first time a procedure focused specifically on the introduction of an iodine atom in free anilines using PIDA [(diacetoxyiodo)benzene] and ammonium iodide which formed in situ acetyl hypoiodite (AcO‐I) as the halogenating species. Our DFT calculations suggest a reaction mechanism that highlights the catalytic role of the ammonium cation in the AcO‐Iformation and halogenation. Considering there are few procedures for the iodine atom introduction in anilines using non‐acidic conditions, herein we described an initial report on a mild and operationally simple alternative using iodine(III) reagents.

Biodegradable flexible proton conducting solid biopolymer membranes based on pectin and ammonium salt for electrochemical applications

One of the most significant difficulties confronting civilization today is the availability of renewable power generation for a growing and highly productive society. Solid-state batteries are expected to be advantageous in a wide variety of energy storage systems. The present work examines the synthesis and characterization of solid biopolymer membranes as electrolytes for solid-state primary proton battery applications from the viewpoint of renewable energy development. Solid biopolymer membranes (SBPMs) based on anionic polysaccharide host polymer pectin and proton donor ammonium iodide (AI) salt are synthesized via a facile solution cast technique. The impact of dopant salt concentration (30 M.wt % to 80 M.wt %) on the membranes' electrical, dielectric, transport, thermal, structural, and electrochemical properties was investigated. At ambient temperature, a maximum ionic conductivity of 4.5 × 10−3 S cm−1 has been achieved. The dielectric and transport properties of the prepared SBPMs are studied and correlated with the trend of ionic conductivity. With the highest conductive SBPM, the primary proton battery has been assembled. The discharge performance and open circuit voltage (OCV) were examined and recommended as a potential candidate for alternate research for low power density applications.

Confinement Effects on the Ionic Liquid Dynamics in Ionosilica Ionogels: Impact of the Ionosilica Nature and the Host/Guest Ratio

Ionosilica ionogels have been lately introduced as emerging all-ionic designer materials. They consist of an ionic liquid (IL) guest trapped within a solid ionosilica support host. In this work, we investigate the influence of the (i) ionosilica nature and (ii) the ionosilica/IL ratio on the mobility of the confined IL. We report the elaboration of various ionosilica ionogels via a nonhydrolytic sol–gel process, using namely tris(3-(trimethoxysilyl)propyl)amine (TTA), methyl-tris(3-(trimethoxysilyl)propyl)ammonium iodide (MTTA), and tetrakis(3-(trimethoxysilyl)-propyl)ammonium iodide (TKTA) as ionosilica precursors, with the IL butyl-methyl imidazolium bis(trifluoromethanesulfonyl)imide ([BMIM] TFSI). Various ionogels were prepared from different ratios between the ionosilica host and the IL guest. The host/guest interactions, i.e., the change in the conformational contribution of the IL counter-anion, were explored by means of Raman spectroscopy. In addition, the transport properties of the confined species were probed via spin echo solid-state NMR experiments and Complex Impedance Spectroscopy (CIS) measurements. Raman experiments revealed different conformational equilibrium for the TFSI anion in the various ionosilica ionogels, with an increase in the cisoid form compared to the bulk IL due to confinement effects. The TFSI anion seems to experience different degrees of confinement and thus different interactions with the ionosilica scaffold as a function of the investigated parameters. Concomitantly, the 1H spin echo NMR and CIS measurements revealed a significantly higher ionic mobility in the materials synthesized from the tris-trialkoxysilylated ammonium precursor compared to the one synthesized from the tetra-trialkoxysilylated ammonium precursor. These results may reflect stronger host–guest interactions in the latter case related to the higher degree of the network reticulation. All these techniques give concordant results and highlight an effect of the chemical constitution of the ionosilica scaffold and the amount of confined IL on its dynamics within the network.

Regiodivergent Cu-Promoted, AcOH-Switchable Distal Versus Proximal Direct Cyanation of 1-Aryl-1H-indazoles and 2-Aryl-2H-indazoles via Aerobic Oxidative C-H Bond Activation.

A copper-promoted regiodivergent, AcOH-switchable, distal and proximal direct cyanation of N-aryl-(1H/2H)-indazoles via aerobic oxidative C(sp2)-H bond activation has been developed. The inclusion or exclusion of AcOH as an additive is the foremost cause for the positional switch in the C-CN bond formation method that results in (C-2')-cyanated 2-aryl-2H-indazoles 3a-j, (C-2')-cyanated 1-aryl-1H-indazoles 4a-j [distal], or C-3 cyanated 2-aryl-2H-indazoles 5a-i [proximal] products in good to excellent yields and showed various functional group tolerance. The cyanide (CN-) ion surrogate was generated via the unification of dimethylformamide and ammonium iodide (NH4I). The utilization of molecular oxygen (aerobic oxidative strategy) as a clean and safe oxidant is liable for generous value addition. The further pertinence of the developed protocol has been demonstrated by transforming the synthesized cyanated product into numerous other functional groups, which will, undoubtedly, accomplish utilization in the synthetic area of biologically important compounds and medicinal chemistry.

Oriented Crystal Growth during Perovskite Surface Reconstruction

Surface passivation has become a key strategy for an improvement in power conversion efficiency (PCE) of perovskite solar cells (PSCs) since PSCs experienced a steep increase in PCE and reached a comparably matured point. Recently, surface passivation using a mixed salt of fluorinated alkyl ammonium iodide and formamidinium bromide demonstrated a remarkable improvement in both performance and stability, which can be tuned by the length of the alkyl chain. Nevertheless, the role of the alkyl chain in manipulating surface-limited crystal growth was not fully understood, preventing a further progress in interface control. In this study, we found that the length of the fluorine-substituted alkyl chain governed the crystal formation dynamics by manipulating surface tensions of different crystal orientations. The overall enhancement of the (001) plane, being the most favored, commonly resulted from the surface reformation of the perovskite film regardless of the chain length, while the highly oriented (001) over (111) was monitored with a particular chain length. The enhanced crystal orientation during surface recrystallization was responsible for the low trap density and thus effectively suppressed charge recombination at the interface, resulting in a considerable increase in open-circuit voltage and fill factor.

Highly selective complexation of cadmium from wet phosphoric acid by organic coordination ligands

Recently, the application of organic coordination ligands for the cadmium removal from wet phosphoric acid (WPA) has shown a great interest, and a certain number of commercially available ligands have shown some affinity and selectivity for cadmium. This technic consists in making complexes between cadmium and ligands. It is easy to integrate industrially and does not require significant investment and maintenance overhead; the cost is driven by the organic ligand stability, efficiency and price. However, the challenge still the high cost of ligand and its insufficient world production capacity in comparison to the increasingly demand. The present research article aims to experiment new organic ligands potentially proved in various media for the cadmium removal. The cadmium removal tests from WPA were carried out under the industrial conditions of 25 % (w/w) P2O5, 14 ppm Cd, and 80 °C. A number of 21 organic ligands were carefully selected based on their potential removal of cadmium. The tests were separately performed under the stoichiometric conditions corresponding to a molar ratio R (nLigand/ncd) of 2, and the excess conditions corresponding to a molar ratio R (nLigand/ncd) of 10. Distinctly, the results relatively to R equaling 10 showed significant increase in cadmium removal specifically to DIBDPi (Diisobutyl dithiophosphinate), DEDTP (Diethyl dithiophosphate), ZDDP (Zinc dialkyl dithiophosphinate), TBAI (Tetrabutyl ammonium iodide), Na2CS3 (Sodium trithiocarbonate), and Aliquat 366 (Methyltrioctyl ammonium chloride), with an efficiency of 86 %, 71 %, 68 %, 29 %, 24 %, and 21 %, respectively. The other ligands still showed no affinity for cadmium removal from WPA.

Highly conducting corn starch doped ionic liquid solid polymer electrolyte for energy storage devices

In this study, a new biopolymer electrolyte (BPE) is successfully developed using corn starch complexed with ammonium iodide (NH4I) as host, and low viscosity ionic liquid 1-Ethyl, 3-Methyl Imidazolium Thiocyanate (EMImSCN), as a plasticizer. This ionic liquid doped BPE shows high ionic conductivity of the order 10−4 S/cm and electrochemical stability window more than 3 V, which is suitable for electrochemical application. The ionic transference number (tion) of 0.98 confirms the system to be predominantly ionic in nature. Fourier transform infrared spectroscopy (FTIR) shows complex nature, while polarized optical microscopy (POM) gives us an idea about the semi-crystalline nature of BPE. Maximum conducting ionic liquid doped BPE sandwiched electric double layer capacitor (EDLC) and dye sensitize solar cell (DSSC) shows efficient performance.

Facile synthesis, larvicidal activity, biological effects, and molecular docking of sulfonamide-incorporating quaternary ammonium iodides as acetylcholinesterase inhibitors against Culex pipiens L

Insecticides participate with a vital role in our lives especially in preventing the spread of human diseases via controlling the dangerous pests. It is a challenge to identify alternatives to the ordinary insecticides with new mode of action to be used for mosquitoes’ control in an environmentally sustainable manner. Using a facile two-step procedure, three novel series of sulfonamide-incorporating quaternary ammonium iodides (3a-i, 4a-i and 5a-i) were synthesized and their chemical structures were successfully characterized. The uncharged sulfonamide intermediates (2a-i) were constructed through simple amidation of the corresponding (hetero)aryl sulfonyl chlorides then the cationic target molecules were formed by quaternizing the tertiary nitrogen with methyl, ethyl, and allyl iodides. The larvicidal activities and biological effects of most synthesized compounds against Culex pipiens L. were extensively investigated and they exhibited good and comparable activities to temephos. Among these hybrids, 4a showed the most potent activity with LC50 = 26.71 ppm. Additionally, the developmental durations of larval and pupal stages were significantly prolonged after treatment with all concentrations of 4h. At high concentration (160 ppm) of 4a and 4b, no adults emerged due to the complete death of pupae, and consequently zero growth index. Moreover, the results of the molecular docking demonstrated that the activities of compounds correlate partially to their binding with acetylcholinesterase (AChE) and it is not the sole parameter for determining the activity.

Triiodide ion-induced inhibition of amyloid aggregate formation: A case study of α-synuclein

• The effect of ethylammonium iodide (EAI) on the formation of amyloid aggregates of α-synuclein (α-SynA) was investigated. • Concentrated EAI solutions exhibited an ability to inhibit α-SynA formation. • The formation of triodide (I 3 – ) ion in this media relates to the inhibition of α-SynA formation. • The inhibition ability of ammonium-based iodides for α-SynA formation are stronger than alkali-iodides. Small compounds that inhibit amyloid protein formation are of interest for the development of anti-amyloidogenic agents. We focused on iodide salts, which are widely used in tablets, supplements, disinfectants, and pharmaceuticals, as anti-amyloidogenic agents in vitro . We performed optical spectroscopy to investigate the effects of ethylammonium iodide (EAI) as an anti-amyloidogenic agent on the formation of amyloid aggregates (neutral pD and 310 K) of human α-synuclein (α-Syn) over a wide range of EAI concentrations. Fourier-transform infrared spectral analysis and a congo red assay revealed that concentrated EAI solutions could inhibit the formation of α-Syn amyloid aggregates (α-SynA). UV–Vis and Raman spectra showed that triiodide (I 3 − ) ion formation occurred in aqueous EAI solution, and clarified that the I 3 – ion relates to the inhibition of α-SynA formation because of the interactions with the peptide backbone and positively charged region in the N-terminal region of α-Syn. In addition to EAI, ammonium iodide (NH 4 I) and methylammonium iodide (MAI) also inhibited α-SynA: NH 4 I and MAI form the I 3 − ion. The inhibition ability of these two salts are stronger than alkali-iodides (KI and NaI). The present results suggest that ammonium iodides that form I 3 − ions have the potential to be effective anti-amyloidogenic agents for α-Syn.