Tetraalkylammonium Cations Research Articles

The Effect of the Tetraalkylammonium Cation in the Electrochemical CO2 Reduction Reaction on Copper Electrode.

Aprotic organic solvents such as acetonitrile offer a potential solution to promote electrochemical CO2 reduction over the competing hydrogen evolution reaction. Tetraalkylammonium cations (TAA+) are widely used as supporting electrolytes in organic media due to their high solubility and conductivity. The alkyl chain length of TAA+ cations is known to influence electron transfer processes in electrochemical systems by the adsorption of TAA+, causing modifications of the double layer. In this work, we elucidate the influence of the cation chain length on the mechanism and selectivity of the CO2RR reaction under controlled dry and wet acetonitrile conditions on copper cathodes. We find that the hydrophobic hydration character of the cation, which can be tuned by the chain length, has an effect on product distribution, altering the reaction pathway. Under dry conditions, smaller cations (TEA+) preferentially promote oxalate production via dimerization of the CO2 ·- intermediate, whereas formate is favored in the presence of water via protonation reaction. Larger cations (TBA+ > TPA+ > TEA+) favor the generation of CO regardless of water content. In situ FTIR analysis showed that TBA+ cations are able to stabilize adsorbed CO more effectively than TEA+, explaining why larger cations generate a higher proportion of CO. Our findings also suggest that higher cation concentrations suppress hydrogen evolution, particularly with larger cations, highlighting the role of cation chain length size and hydrophobic hydration shell.

Mechanism and rate of anomalous extraction of chloride salts from water to 1,2-dichloroethane

Open circuit potential (OCP) measurements, potentiostatic pulse (PP) amperometry and cyclic voltammetry (CV), were used to investigate and to sort by rate the anomalous extraction of the chloride salts RCl of the cations R+ = tetrabutylammonium (TBA+), tetrapentylammonium (TPeA+), tetrahexylammonium (THexA+), tetraheptylammonium (THepA+) and bis(triphenyl-phosphoranylidene)ammonium (BA+) from water to 1,2-dichloroethane (DCE). A tentative mechanism is proposed comprising (a) the diffusion-controlled transport of the ion-pairs (RCl)ip from the aqueous to the organic solvent phase providing a major contribution to the chloride extraction, (b) decomposition of the multiple ion-pairs or clusters (RCl)ipx, which are formed by agglomeration of the single ion-pairs (RCl)ip in the aqueous phase (w), and (c) the exponential decay of the ion-pairs (RCl)ip accumulated on the organic solvent side of the interface at the beginning of the OCP measurements. This model enables to simulate successfully the experimental time dependence of the chloride concentration. A conclusion is made that the effect of the composition of the organic solvent electrolyte RX, where X- = tetraphenylborate (TPB-) or tetrakis(pentafluorophenyl) borate (TB-), on the rate and extent of the anomalous accumulation of the chloride anion in the phase (o) of the two-phase liquid system LiCl(w)/RX(o) can be related to the hydrophobicity of the electrolytes RCl and RX. The latter property can be characterized by the standard Gibbs energy of transfer from the aqueous (w) to the organic solvent (o) phase. The accumulation of the chloride anion in the phase (o) appears to be promoted by the decreasing value of the transfer Gibbs energy of RCl in the sequence TBACl > TPeACl > THexACl > THepACl > BACl, while the decreasing value of the transfer Gibbs energy of RX in the sequence TBATPB > TPeATPB > THexATPB > THepATPB > BATPB > BATB starts to block the cycle combining the energetically unfavorable extraction of RX from the phase (o) to the phase (w) with the energetically favorable extraction of RCl in the opposite direction. IR spectroscopy provides evidence of the formation of the water clusters in the organic solvent phase equilibrated with the aqueous phase in the presence of the tetraalkylammonium cation in both phases, which are supposed to drive the anomalous accumulation of the chloride anion in the phase (o).

Greasy Cations Bind to Neutral Macromolecules in Aqueous Solution.

Ions influence the solution properties of macromolecules. Although much is known about anions, cationic effects are considered mostly in terms of weak interactions or exclusion from neutral interfaces. Herein, we have systematically studied the effect of quaternary tetraalkylammonium cations (NH4+, NMe4+, NEt4+, NPr4+, NBu4+) on the phase transition of poly(N-isopropylacrylamide) (PNIPAM) in aqueous solution. Solubility measurements were coupled to 1H NMR and ATR-FTIR spectroscopic measurements. The solubility and NMR measurements revealed a direct binding between the greasiest cations and the isopropyl group of the macromolecule, evidenced from the nonlinear, Langmuir-type chemical shift response only at the isopropyl NMR signals with increasing salt concentrations. The ATR-FTIR measurements focusing on the amide oxygen showed that it is not the main direct-binding site. Additionally, the salting-out effects of the greasier cations correlate with their hydration entropies. These results demonstrate that the most weakly hydrated cations can bind to macromolecules as strongly as the weakly hydrated Hofmeister anions.

Vacancy‐Assisted Transformation of MoS2 Nanosheets into Defective MoSx Nanoclusters to Regulate Sodium‐Ion Electrode Functionality

AbstractDefect structure has attracted significant attention because of its importance as design factor for exploring high‐performance functional materials. This study reports a defect‐engineering strategy to optimize the electrode performance of transition metal dichalcogenides and a clear elucidation of the underlying mechanism on the benefit of defect engineering with cycling‐induced transformation into small nanoclusters. The intercalative hybridization of monolayered MoS2 nanosheets with bulky tetraalkylammonium cations is effective for generating abundant crystal vacancies in the MoS2 lattice and improving the sodium‐ion electrode performance, achieving one of the excellent performances among MoS2‐based sodium‐ion anode materials. The improved electrode activity of the tetrapropylammonium−MoS2 nanohybrid is ascribed to the vacancy‐assisted transformation from monolayered MoS2 nanosheets into trimeric/dimeric MoSx nanoclusters during electrochemical cycling. 23Na/1H magic angle spinning‐nuclear magnetic resonance analyses demonstrated that cycling‐induced defective MoSx nanoclusters yields a complex Na environment with high ion mobility and enhanced electrolyte absorptivity, promoting the excellent electrode functionality of tetrapropylammonium‐assembled MoS2 nanosheets.

Enhanced solid-state phosphorescence of organoplatinum π-systems by ion-pairing assembly.

Anion binding and ion pairing of dipyrrolyldiketone PtII complexes as anion-responsive π-electronic molecules resulted in photophysical modulations, as observed in solid-state phosphorescence properties. Modifications to arylpyridine ligands in the PtII complexes significantly impacted the assembling behaviour and photophysical properties of anion-free and anion-binding (ion-pairing) forms. The PtII complexes, in the presence of guest anions and their countercations, formed various anion-binding modes and ion-pairing assembled structures depending on constituents and forms (solutions and crystals). The PtII complexes emitted strong phosphorescence in deoxygenated solutions but showed extremely weak phosphorescence in the solid state owing to self-association. In contrast, the solid-state ion-pairing assemblies with tetraalkylammonium cations exhibited enhanced phosphorescence owing to the formation of hydrogen-bonding 1D-chain PtII complexes dispersed by stacking with aliphatic cations. Theoretical studies revealed that the enhanced phosphorescence in the solid-state ion-pairing assembly was attributed to preventing the delocalisation of the electron wavefunction over PtII complexes.

Cation Adaptive Structures Based on Manganese Cyanide Prussian Blue Analogues: Application of Powder Diffraction Data to Solve Complex, Unprecedented Stoichiometries and New Structure Types.

A Mn(II) salt and A+ CN- under anaerobic conditions react to form 2-D and 3-D extended structured compounds of Am MnII n (CN)m+2n stoichiometry. Here, the creation and characterization of this large family of compounds, for example AMnII 3 (CN)7 , A2 MnII 3 (CN)8 , A2 MnII 5 (CN)12 , A3 MnII 5 (CN)13 , and A2 MnII [MnII (CN)6 ], where A represents alkali and tetraalkylammonium cations, is reviewed. Cs2 MnII [MnII (CN)6 ] has the typical Prussian blue face centered cubic unit cell. However, the other alkali salts are monoclinic or rhombohedral. This is in accord with smaller alkali cation radii creating void space that is minimized by increasing the van der Waals stabilization energy by reducing ∠Mn-N≡C, which, strengthens the magnetic coupling and increases the magnetic ordering temperatures. This is attributed to the non-rigidity of the framework structure due the significant ionic character associated with the high-spin MnII sites. For larger tetraalkylammonium cations, the high-spin Mn sites lack sufficient electrostatic A+ ⋅⋅⋅NC stabilization and form unexpected 4- and 5-coordinated Mn sites within a flexible, extended framework around the cation; hence, the size, shape, and charge of the cation dictate the unprecedented stoichio-metry and unpredictable cation adaptive structures. Antiferromagnetic coupling between adjacent MnII sites leads to ferrimagnetic ordering, but in some cases antiferromagnetic coupling of ferrimagnetic layers are compensated and synthetic antiferromagnets are observed. The magnetic ordering temperatures for ferrimagnetic A2 MnII [MnII (CN)6 ] with both octahedral high- and low-spin MnII sites increase with decreasing ∠Mn-N≡C. The crystal structures for all of the extended structured materials were obtained by powder diffraction.

The synthesis, thermal behaviour, spectral and structural characterization, and in silico prediction of pharmacokinetic parameters of tetraalkylammonium salts of non-steroidal anti-inflammatory drug nimesulide

The synthesis, spectral properties, thermal analysis, structural characterization and in silico prediction of pharmacokinetic parameters of tetramethylammonium (compound 1) and tetraethylammonium (compound 2) salt of nimesulide were described in this article. Both compounds crystallize in the monoclinic P21/n space group, with one tetraalkylammonium cation and one nimesulide anion in the asymmetric unit and their crystal structures are stabilized by C–H···O hydrogen bonds between ions. Additionally, structures of title compounds are stabilized by π–π interactions (compound 1), or C–H···π interactions (compound 2) between nimesulide anions. The TG and DSC measurements show that compound 1 melts at a temperature higher than nimesulide, whereas the compound 2 melts at a temperature lower than nimesulide. The MALDI-TOF, 1H NMR, 13C NMR and ATR-FTIR analyses confirm the SCXRD study, that in compounds 1 and 2 nimesulide exists in an ionized form. Studies performed by SWISS ADME and ProTOX II tools, predict to be oral bioavailability of both salts obtained, and one of them (compound 1) is predicted to be well-absorbed by digestive system, while both compounds obtained are classified into toxicity class 4.

Effects of interfacial molarity on salts inducing vesicle-to-micelle transitions in acyl taurines

Specific ion effects (SIEs) are crucial in engineering, chemistry and biology. N-acyl taurine (NAT) exists naturally in organisms and may have various physiological functions. However, compared with other acyl amino acid-based surfactants bearing carboxylate headgroups, the SIEs on NATs have received little research. Here, sodium lauroyl taurate (SLT) and sodium methyl lauroyl taurate (SMLT) bearing secondary and tertiary amides, respectively, were synthesized by a green method. The interfacial molarities of water, amides and sulfonate groups in SLT and SMLT aggregates were estimated simultaneously in the presence of tetraalkylammonium cations (TAA+) of different chain lengths. With increasing salt concentration, the interfacial water molarity increased, whereas the interfacial amide molarity decreased in all cases. However, at a fixed salt concentration, the interfacial water molarity increased with the hydrophobicity of cations, while the interfacial amide bond molarity followed the reverse order. The combined TEM and DLS results show that the majority of SLT and SMLT molecules formed vesicles spontaneously in the absence of salts, and some of these vesicles turned into micelles with TAA+ addition. Tertiary amides of SMLT may also absorb protons at the interface and interact with each other by hydrogen bonding. Such hydrogen bonds facilitate the tight packing of surfactant molecules and induce vesicle formation, just like the intermolecular amide-amide hydrogen bonds between SLT. Added TAA+ cleaves the hydrogen bonds between NAT and induces vesicle-to-micelle transitions. This hypothesis is supported by CT results showing that vesicle-to-micelle transitions were accompanied by decreases in interfacial amide molarity.

Enabling one- and two-dimensional mass spectrometry in a linear quadrupole ion trap

Two-dimensional tandem mass spectrometry (2D-MS/MS) provides rapid unsupervised access to all product ions of all ionized precursor ions in a single scan, and as such, is a powerful analysis method for quadrupole ion traps. However, the way in which 2D-MS/MS was previously implemented on our Thermo LTQ prevented us from switching back and forth from conventional one-dimensional mass spectrometry (1D-MS) without significant effort and on any reasonable timescale. This drawback inhibited our ability to perform standard workflows such as mass calibration and automatic voltage optimizations, but also made it impractical to perform cross-validation between modes on the same instrument. In effect, this reduced our data quality, preventing us from generating 2D-MS/MS spectral libraries with high fidelity, and from comparing spectra collected under differing conditions (user, time, etc.). In this study, an Arduino Uno microcontroller is used to control several electrical/electromechanical switches and the timing of all experimental subsystems in response to the instrument trigger output and a user selected operating mode. With a selection made, the user simply needs to adjust a few software parameters and change the bath gas of the linear ion trap. The ability to rapidly switch operational modes is demonstrated using a mixture of tetraalkylammonium cations for which spectra are collected in both 1D (helium) and 2D (nitrogen) modes in less than 1 min. By calibrating and measuring the RF amplitude control signal in 1D mode it is possible to calculate the applied RF amplitude in 2D mode, thereby allowing the user to determine relevant quadrupole operating parameters for a particular sample. Details of the system and its modifications are provided.

Electrical Conductivity and Ionic Association in Tetraalkylammonium Ionic Liquids in Acetonitrile Solutions

A study is performed of the electrical conductivity (EC) of ionic liquids based on quaternary triethylalkylammonium salts with tetrafluoroborate and hexafluorophosphate anions in acetonitrile. Conductometric data on these compounds are analyzed. Constants Ka of the ionic association of the limiting molar electrical conductivity (λ0) and the standard Gibbs energy of association (ΔG0) in solutions are calculated using the Lee–Wheaton formula. The Stokes radii, limiting mobility, and limiting coefficients of diffusion are found for tetraalkylammonium cations.

A Dicationic fac-Re(bpy)(CO)3Cl for CO2 Electroreduction at a Reduced Overpotential.

A dicationic Re bipyridine-type complex, fac-Re(6,6'-(2-((trimethylammonio)-methyl)phenyl)-2,2'-bipyridine )(CO)3Cl hexafluorophosphate (12+), has been synthesized, and its electrochemical behavior under Ar and CO2 has been investigated. The presence of pendent tetra-alkylammonium cations induces an anodic shift in the electrocatalytic potential for CO2 reduction relative to structurally similar model complexes. The electrochemical mechanisms in anhydrous CH3CN and in the presence of weak acids (water or trifluoroethanol) have been analyzed using cyclic voltammetry assisted by infrared spectroelectrochemistry and theoretical calculations. The dication enables catalysis at a diminished potential through Coulombic stabilization of the doubly reduced pentacoordinate species, its CO2 adduct, the hydroxide anion, and the conjugate base formed during acid-assisted C-OH bond cleavage of the metallocarboxylic acid to the metallocarbonyl and H2O. The major reduction product is CO, but in the presence of trifluoroethanol, formate is also produced with 14% Faradaic efficiency.

Supramolecular Catalysts for the Radical Destruction of Hydroperoxides Based on Choline Derivatives

The effect of natural quaternary ammonium compounds (QAC) of choline (Ch) and its derivatives, acetylcholine (AСh) and L-carnitine (LCh), containing the tetraalkylammonium cation (CH3)3RN+, on the radical decomposition of hydroperoxides (ROOH) was studied. In mixtures of ACh and Ch with ROOH in chlorobenzene, mixed supramolecular nanoaggregates are formed, and accelerated decomposition of ROOH into radicals takes place; the rates of radical formation measured by the inhibitor method decrease in the series ACh Ch \( \gg \) LCh. ACh and Ch immobilized on microcrystalline cellulose retain the ability to catalyze the radical decomposition of ROOH and initiate the polymerization of styrene containing ROOH from the surface. LСh adsorbed on cellulose does not affect the decomposition of ROOH and the rate of polymerization. Scanning electron microscopy (SEM) showed that ACh and Ch adsorbed on a silicon plate accelerate the radical decomposition of ROOH and initiate oxidative condensation of egg phosphatidylcholine on the surface of the plate, while adsorbed LCh does not affect the decomposition of ROOH. LCh, unlike ACh and Ch, is an internal salt in which the R4N+ cation is neutralized by its own carboxy anion, i.e., LCh has no external counterion and, probably, for this reason, it differs from ACh and Ch in the mechanism of adsorption and interaction with ROOH.

Lewis acid-driven self-assembly of diiridium macrocyclic catalysts imparts substrate selectivity and glutathione tolerance.

Molecular inorganic catalysts (MICs) tend to have solvent-exposed metal centers that lack substrate specificity and are easily inhibited by biological nucleophiles. Unfortunately, these limitations exclude many MICs from being considered for in vivo applications. To overcome this challenge, a strategy to spatially confine MICs using Lewis acid-driven self-assembly is presented. It was shown that in the presence of external cations (e.g., Li+, Na+, K+, or Cs+) or phosphate buffered saline, diiridium macrocycles spontaneously formed supramolecular iridium-cation species, which were characterized by X-ray crystallography and dynamic light scattering. These nanoassemblies selectively reduced sterically unhindered C[double bond, length as m-dash]O groups via transfer hydrogenation and tolerated up to 1 mM of glutathione. In contrast, when non-coordinating tetraalkylammonium cations were used, the diiridium catalysts were unable to form higher-ordered structures and discriminate between different aldehyde substrates. This work suggests that in situ coordination self-assembly could be a versatile approach to enable or enhance the integration of MICs with biological hosts.

Probing Interfacial Co‐Crystallisation using Simultaneous Potential and Current Measurements at Liquid‐Liquid Interfaces Polarised by Common Ion Approach

AbstractThe simultaneous measurement of potential and current variations at the interface between two immiscible electrolyte solutions, which was polarised using tetraalkylammonium cations as a common ion, is reported here. Various concentration ratios of tetramethyl‐, tetraethyl‐, or tetrapropylammonium were dissolved in each phase. Such biphasic systems were then used to verify that the measured interfacial potential difference agreed with theory. This experimental set‐up was then used to probe the interfacial cocrystallisation process of hydrophilic, cationic caffeine with lipophilic 1‐hydroxy‐2‐naphtoic acid (1H2N). The presence of caffeine in the aqueous phase led to higher current values, caused by interfacial charge transfer. Electrochemical noise analysis suggested that a two‐step process was occurring at the ITIES (i) a potential‐driven nucleation with the transfer of caffeine from the aqueous to the organic phase; (ii) a growth stage where the interfacial potential no longer plays a role.

Supercrystal engineering of atomically precise gold nanoparticles promoted by surface dynamics.

The controllable packing of functional nanoparticles (NPs) into crystalline lattices is of interest in the development of NP-based materials. Here we demonstrate that the size, morphology and symmetry of such supercrystals can be tailored by adjusting the surface dynamics of their constituent NPs. In the presence of excess tetraethylammonium cations, atomically precise [Au25(SR)18]- NPs (where SR is a thiolate ligand) can be crystallized into micrometre-sized hexagonal rod-like supercrystals, rather than as face-centred-cubic superlattices otherwise. Experimental characterization supported by theoretical modelling shows that the rod-like crystals consist of polymeric chains in which Au25 NPs are held together by a linear SR-[Au(I)-SR]4 interparticle linker. This linker is formed by conjugation of two dynamically detached SR-[Au(I)-SR]2 protecting motifs from adjacent Au25 particles, and is stabilized by a combination of CH⋯π and ion-pairing interactions between tetraethylammonium cations and SR ligands. The symmetry, morphology and size of the resulting supercrystals can be systematically tuned by changing the concentration and type of the tetraalkylammonium cations.

In Situ Tetraalkylammonium Ligand Engineering of Organic-Inorganic Hybrid Perovskite Nanoparticles for Enhancing Long-Term Stability and Optical Tunability.

Organic-inorganic hybrid perovskite nanoparticles (OIHP NPs) have attracted scientific attention owing to their efficient photoluminescence with optical tunability, which is highly advantageous for optoelectronic applications. However, the limited long-term stability of OIHP NPs has significantly hindered their practical application. Despite several synthetic strategies and encapsulation methods to stabilize OIHP NPs, complicated multi-step procedures are often required. In this study, we introduce an in situ ligand engineering method for stabilizing and controlling the optical properties of OIHP NPs using tetraalkylammonium (TAA) halides with various molecular structures at different concentrations. Our one-pot ligand engineering substantially enhanced the stability of the OIHP NPs without post-synthetic processes. Moreover, in certain cases, approximately 90% of the initial photoluminescence (PL) intensity was preserved even after a month under ambient conditions (room temperature, 20-50% relative humidity). To determine the role of ligand engineering in stabilizing the OIHP NPs, the surface binding properties of the TAA ligands were thoroughly analyzed using Raman spectroscopy. Specifically, the permanent positive charge of the TAA cations and consequent effective electrostatic interactions with the surfaces of the OIHP NPs are pivotal for preserving the initial PL intensity. Our investigation is beneficial for developing OIHP nanomaterials with improved stability and controlled photoluminescence for various optoelectronic applications, such as light-emitting devices, photosensitizers, photodetectors, photocatalysis, and solar cells.

Selective Ion Sieving and Disorder in Membranes Constructed from Two-Dimensional Covalent Organic Frameworks

Two-dimensional covalent organic frameworks (2D-COFs) have been of increasing interest in the past decade due to their potentially ordered porous structures. One of the most common routes to these polymers relies on Schiff-base chemistry, i.e. the condensation reaction between a carbonyl and an amine. However, the judicious choice of these two building blocks is critical given that many COF forming reactions can lead to an inherent disorder if such a pathway is available. Examples of disorder in 2D-COFs due to both inherent growth mechanisms and reaction pathways will be given and their influence on ion sieving membranes will be discussed. A 2D-COF with negatively charged carboxylated pores, where disorder is minimized, has been shown to be highly charge and size selective for ion conductivity for a series of tetraalkyl ammonium cations. Progress on membranes for desalinization and small ion separations such as Li ion separation from brines using negatively charged, positively charged and zwitterion pores will also be presented.

Swelling and dissolution kinetics of poly(4-hydroxystyrene) in tetrabutylammonium hydroxide (TBAH) aqueous solutions studied by quartz crystal microbalance (QCM) method—in comparison with tetramethylammonium hydroxide (TMAH) aqueous solutions

The dissolution (including the formation of a transient swelling layer) of a resist polymer is key to realizing ultrafine patterning. However, the details of the dissolution of resist polymers remain unclarified. In this study, the swelling and dissolution kinetics of poly(4-hydroxystyrene) (PHS) films in tetramethylammonium hydroxide (TMAH) and tetrabutylammonium hydroxide (TBAH) aqueous solutions were investigated by a quartz crystal microbalance method. PHS is a typical backbone polymer (a dissolution agent) of chemically amplified resists. The swelling and dissolution kinetics of PHS were observed by changing the protection ratio of the hydroxyl groups of PHS and the alkaline concentration in developers. Not only the dissolution rate but also the mode of dissolution depended on the molecular structure of tetraalkylammonium cations. For polymer matrices with strong hydrogen bond networks such as PHS, the penetration of tetrabutylammonium cations is considered to be strongly suppressed by their long alkyl chains.

Dependence of photoresist dissolution dynamics in alkaline developers on alkyl chain length of tetraalkylammonium hydroxide

Extreme ultraviolet (EUV) lithography is already being applied to the high-volume manufacturing of semiconductor devices. Although EUV lithography has enabled fine pitch scaling, such sub-20 nm order fabrication has also imposed the issue of stochastic defects (in the form of randomly generated line bridges and breaks). To resolve such an issue, understanding the development process is essential. In this study, the dissolution dynamics of three types of EUV photoresist were investigated for four types of alkaline developer using a quartz crystal microbalance method to clarify the swelling and dissolution kinetics during photoresist development. In experiments, tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), and tetrabutylammonium hydroxide (TBAH) aqueous solutions were used as developers. Poly(4-hydroxystyrene) (PHS)-type, acryl-type, and hybrid-type photoresists were examined. The effect of the alkyl chain length of tetraalkylammonium cations depended on the type of photoresist. The dissolution dynamics depended on the combination of types of photoresist and developer.

Ion-Specific Effects on Vesicle-to-Micelle Transitions of an Amino Acid Surfactant Probed by Chemical Trapping.

Ion-specific effects widely exist in biological and chemical systems and cannot be explained by classical theories. The complexity of ion-specific effects in protein systems at the molecular level necessitates the use of mimetic models involving smaller molecules, such as amino acids, oligopeptides, and other organic molecules bearing amide bonds. Therefore, it is of theoretical value to determine the effect of additional salts on the aggregation transitions of acyl amino acid surfactants. Herein, the effects of specific tetraalkylammonium ions (TAA+) on sodium lauroyl glycinate (SLG) aggregation were studied by dynamic light scattering (DLS) and transmission electron microscopy. Although previous studies have shown that the kosmotropic TAA+ ions tend to induce micellar growth or micelle-to-vesicle transitions of some anionic surfactants, TAA+ addition in the present study induced partial vesicle-to-micelle transitions in SLG solutions. The chemical trapping (CT) method was employed to estimate changes in the interfacial molarities of water, amide bonds, and carboxylate groups during such transitions. The vesicle-to-micelle transitions were accompanied by a marked rise in interfacial water molarity and a decline in interfacial amide bonds molarity, suggesting that the hydrated TAA+ entered the interfacial region and disrupted hydrogen bonding, thus preventing the SLG monomers from packing tightly. Molecular dynamic simulation was also performed to demonstrate the salt-induced cleavage of amide-amide bonds between SLG headgroups. Furthermore, both CT and DLS results show that the ability of tetraalkylammonium cations to induce such transitions increased with increasing size and hydrophobicity of the cation, which follows the Hofmeister series. The current study offers critical molecular-level evidence for understanding the specific effects of tetraalkylammonium ions on the aggregation transitions of an acyl amino acid surfactant.