Browse
Submit Data
Databases
API
Help

Dataset Information

27 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Ester formation at the liquid-solid interface.

ABSTRACT: A chemical reaction (esterification) within a molecular monolayer at the liquid-solid interface without any catalyst was studied using ambient scanning tunneling microscopy. The monolayer consisted of a regular array of two species, an organic acid (trimesic acid) and an alcohol (undecan-1-ol or decan-1-ol), coadsorbed out of a solution of the acid within the alcohol at the interface of highly oriented pyrolytic graphite (HOPG) (0001) substrate. The monoester was observed promptly after reaching a threshold either related to the increased packing density of the adsorbate layer (which can be controlled by the concentration of the trimesic acid within the alcoholic solution via sonication or extended stirring) or by reaching a threshold with regards to the deposition temperature. Evidence that esterification takes place directly at the liquid-solid interface was strongly supported.

SUBMITTER: T N Ha N

PROVIDER: S-EPMC5647715 | biostudies-literature | 2017

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Ester formation at the liquid-solid interface.

T N Ha Nguyen N Gopakumar Thiruvancheril G TG D C Yen Nguyen N Mende Carola C Smykalla Lars L Schlesinger Maik M Buschbeck Roy R Rüffer Tobias T Lang Heinrich H Mehring Michael M Hietschold Michael M

Beilstein journal of nanotechnology 20171012

A chemical reaction (esterification) within a molecular monolayer at the liquid-solid interface without any catalyst was studied using ambient scanning tunneling microscopy. The monolayer consisted of a regular array of two species, an organic acid (trimesic acid) and an alcohol (undecan-1-ol or decan-1-ol), coadsorbed out of a solution of the acid within the alcohol at the interface of highly oriented pyrolytic graphite (HOPG) (0001) substrate. The monoester was observed promptly after reaching ...[more]

PMID: 29090115

Similar Datasets

Electron microscopy of nanoparticle superlattice formation at a solid-liquid interface in nonpolar liquids.

Project description:Nanoparticle superlattice films form at the solid-liquid interface and are important for mesoscale materials, but are notoriously difficult to analyze before they are fully dried. Here, the early stages of nanoparticle assembly were studied at solid-liquid interfaces using liquid-phase electron microscopy. Oleylamine-stabilized gold nanoparticles spontaneously formed thin layers on a silicon nitride (SiN) membrane window of the liquid enclosure. Dense packings of hexagonal symmetry were obtained for the first monolayer independent of the nonpolar solvent type. The second layer, however, exhibited geometries ranging from dense packing in a hexagonal honeycomb structure to quasi-crystalline particle arrangements depending on the dielectric constant of the liquid. The complex structures formed by the weaker interactions in the second particle layer were preserved, while the surface remained immersed in liquid. Fine-tuning the properties of the involved materials can thus be used to control the three-dimensional geometry of a superlattice including quasi-crystals.

| S-EPMC7220325 | biostudies-literature

Probing hydrophilic interface of solid/liquid-water by nanoultrasonics.

Project description:Despite the numerous devoted studies, water at solid interfaces remains puzzling. An ongoing debate concerns the nature of interfacial water at a hydrophilic surface, whether it is more solid-like, ice-like, or liquid-like. To answer this question, a complete picture of the distribution of the water molecule structure and molecular interactions has to be obtained in a non-invasive way and on an ultrafast time scale. We developed a new experimental technique that extends the classical acoustic technique to the molecular level. Using nanoacoustic waves with a femtosecond pulsewidth and an ångström resolution to noninvasively diagnose the hydration structure distribution at ambient solid/water interface, we performed a complete mapping of the viscoelastic properties and of the density in the whole interfacial water region at hydrophilic surfaces. Our results suggest that water in the interfacial region possesses mixed properties and that the different pictures obtained up to now can be unified. Moreover, we discuss the effect of the interfacial water structure on the abnormal thermal transport properties of solid/liquid interfaces.

| S-EPMC4150100 | biostudies-literature

Accommodative Behavior of Non-porous Molecular crystal at Solid-Gas and Solid-Liquid Interface.

Project description:Molecular crystals demonstrate drastically different behavior in solid and liquid state, mainly due to their difference in structural frameworks. Therefore, designing of unique structured molecular compound which can work at both these interfaces has been a challenge. Here, we present remarkable 'molecular' property by non-porous molecular solid crystal, dinuclear copper complex (C6H5CH(X)NH2)2CuCl2, to reversibly 'adsorb' HCl gas at solid-gas interface as well as 'accommodate' azide anion at solid-liquid interface with crystal to crystal transformation. The latter process is driven by molecular recognition, self-assembly, and anchimeric assistance. The observed transformations are feasible due to breathing of inner and outer coordination sphere around metal center resulting in change in metal polyhedra for 'accommodating' guest molecule. These transformations cause changes in optical, magnetic, and/or ferroelectric property offering diversity in 'sensing' application. With the proposed underlying principles in these exceptional reversible and cyclic transformations, we prepared a series of compounds, can facilitate designing of novel multifunctional molecular materials.

| S-EPMC4585990 | biostudies-literature

Core-shell architecture based on bio-sourced porous carbon: the shape formation mechanism at the solid/liquid interface layer.

Project description:The overall goal of this work was to activate agri-food wastes by microbial action, which makes it possible to produce bio-digestate and energy (methane). The resulting bio-digestate could be transformed to porous carbon (PC), which was used for the preparation of core-shell particles with alginate (bio-polymer) and a calcium ion layer. Furthermore, surface charge measurements showed electrostatic attractions occurring between the alginate, calcium (Ca2+) ions and the PC, hence leading to the formation of core (PC)-shell (alginate-calcium ions) particles. However, in the absence of calcium ions, no electrostatic attractions were observed between the PC and the alginate. In the dried state (using scanning electronic microscopy analysis (SEM)) and in the hydrate state (using numerical microscopy), the designed core-shell architecture was confirmed. Transmission electron microscopy (TEM) shows that the PC particles were graphitic and porous. In addition, both Raman spectroscopy (RS) and X-ray photoelectron spectroscopy (XPS) showed the presence of several chemical functions, in particular hydroxyl (-O-H) and carboxylic groups (-COO-H). In aqueous media, the results showed that the PC was negatively charged and its surface charge and particle size were found to be very sensitive to the variation in pH. Finally, the core-shell particles were used as an adsorbent for the removal of methylene blue (MB), crystal violet (CV) and congo red (CR) molecules from wastewater. The overall data indicated efficient dye removal, without the occurrence of the solid/liquid separation problem.

| S-EPMC9070343 | biostudies-literature

Anion Exchange at the Liquid/Solid Interface of Ultrathin Ionic Liquid Films on Ag(111).

Project description:Thin ionic liquid (IL) films play an important role in many applications. To obtain a better understanding of the ion distribution within IL mixture films, we sequentially deposited ultrathin layers of two ILs with the same cation but different anions onto Ag(111), and monitored their dynamic behaviour by angle-resolved X-ray photoelectron spectroscopy. Upon depositing [C8 C1 Im][PF6 ] on top of a wetting layer of [C8 C1 Im][Tf2 N] at room temperature (RT), we found a pronounced enrichment of the [Tf2 N]- anions at the IL/vacuum interface, due to a rapid anion exchange at the IL/solid interface. In contrast, at 90?K, the [Tf2 N]- anions remain at the IL/solid interface. Upon heating, we observe a rearrangement of the cations between 140 and 160?K, such that the octyl chains preferentially point towards the vacuum. Above 170?K, the ions start to become mobile, and at 220?K, the anion exchange is completed, with the [Tf2 N]- anions enriched at the IL/vacuum interface in the same way as found for deposition at RT. The temperature range for the anion exchange corresponds well to glass transition temperatures reported in literature. We propose two driving forces to be cooperatively responsible for the replacement/exchange of [Tf2 N]- at the IL/solid interface and its enrichment at the IL/vacuum interface. First, the adsorption energy of [C8 C1 Im][PF6 ] is significantly larger than that of [C8 C1 Im][Tf2 N], and second, the surface tension of [C8 C1 Im][Tf2 N] is lower than that of [C8 C1 Im][PF6 ].

| S-EPMC6282575 | biostudies-literature

Manipulation of small particles at solid liquid interface: light driven diffusioosmosis.

Project description:The strong adhesion of sub-micron sized particles to surfaces is a nuisance, both for removing contaminating colloids from surfaces and for conscious manipulation of particles to create and test novel micro/nano-scale assemblies. The obvious idea of using detergents to ease these processes suffers from a lack of control: the action of any conventional surface-modifying agent is immediate and global. With photosensitive azobenzene containing surfactants we overcome these limitations. Such photo-soaps contain optical switches (azobenzene molecules), which upon illumination with light of appropriate wavelength undergo reversible trans-cis photo-isomerization resulting in a subsequent change of the physico-chemical molecular properties. In this work we show that when a spatial gradient in the composition of trans- and cis- isomers is created near a solid-liquid interface, a substantial hydrodynamic flow can be initiated, the spatial extent of which can be set, e.g., by the shape of a laser spot. We propose the concept of light induced diffusioosmosis driving the flow, which can remove, gather or pattern a particle assembly at a solid-liquid interface. In other words, in addition to providing a soap we implement selectivity: particles are mobilized and moved at the time of illumination, and only across the illuminated area.

| S-EPMC5093767 | biostudies-literature

Spontaneous formation of a self-healing carbon nanoskin at the liquid-liquid interface.

Project description:Biological membranes exhibit the ability to self-repair and dynamically change their shape while remaining impermeable. Yet, these defining features are difficult to reconcile with mechanical robustness. Here, we report on the spontaneous formation of a carbon nanoskin at the oil-water interface that uniquely combines self-healing attributes with high stiffness. Upon the diffusion-controlled self-assembly of a reactive molecular surfactant at the interface, a solid elastic membrane forms within seconds and evolves into a continuous carbon monolayer with a thickness of a few nanometers. This nanoskin has a stiffness typical for a 2D carbon material with an elastic modulus in bending of more than 40-100 GPa; while brittle, it shows the ability to self-heal upon rupture, can be reversibly reshaped, and sustains complex shapes. We anticipate such an unusual 2D carbon nanomaterial to inspire novel approaches towards the formation of synthetic cells with rigid shells, additive manufacturing of composites, and compartmentalization in industrial catalysis.

| S-EPMC9399178 | biostudies-literature

Self-Assembly of Covalently Linked Porphyrin Dimers at the Solid-Liquid Interface.

Project description:The synthesis and surface self-assembly behavior of two types of metal-porphyrin dimers is described. The first dimer type consists of two porphyrins linked via a rigid conjugated spacer, and the second type has an alkyne linker, which allows rotation of the porphyrin moieties with respect to each other. The conjugated dimers were equipped with two copper or two manganese centers, while the flexible dimers allowed a modular built-up that also made the incorporation of two different metal centers possible. The self-assembly of the new porphyrin dimers at a solid-liquid interface was investigated at the single-molecule scale using scanning tunneling microscopy (STM). All dimers formed monolayers, of which the stability and the internal degree of ordering of the molecules depended on the metal centers in the porphyrins. While in all monolayers the dimers were oriented coplanar with respect to the underlying surface ('face-on'), the flexible dimer containing a manganese and a copper center could be induced, via the application of a voltage pulse in the STM setup, to self-assemble into monolayers in which the porphyrin dimers adopted a non-common perpendicular ('edge-on') geometry with respect to the surface.

| S-EPMC6720350 | biostudies-literature

Concentration-dependent <i>rhombitrihexagonal tiling</i> patterns at the liquid/solid interface.

Project description:We report STM investigations on a linear oligophenyleneethylene (OPE)-based self-assembling Pd(ii) complex 1 that forms highly-ordered concentration dependent patterns on HOPG. At high concentration, 2D lamellar structures are observed whereas the dilution of the system below a critical concentration leads to the formation of visually attractive rhombitrihexagonal Archimedean tiling arrangements featuring three different kinds of polygons: triangles, hexagons and rhombi. The key participation of the Cl ligands attached to the Pd(ii) centre in multiple C-H···Cl interactions was demonstrated by comparing the patterns of 1 with those of an analogous non-metallic system 2.

| S-EPMC5523081 | biostudies-literature

"Concentration-in-Control" self-assembly concept at the liquid-solid interface challenged.

Project description:Self-assembled molecular networks (SAMNs) on surfaces evoke a lot of interest, both from a fundamental as well as application point of view. When formed at the liquid-solid interface, precise control over different polymorphs can be achieved by simply adjusting the concentration of molecular building blocks in solution. Significant influence of solute concentration on self-assembly behavior has been observed, whether the self-assembly behavior is controlled by either van der Waals forces or hydrogen bonding interactions. In both cases, high- and low-density supramolecular networks have been observed at high and low solute concentrations, respectively. In contrast to this "concentration-in-control" self-assembly concept here we report an atypical concentration dependent self-assembly behavior at a solution-solid interface. At the interface between heptanoic acid (HA) and highly oriented pyrolytic graphite (HOPG), we show, using scanning tunneling microscopy (STM), the formation of a low-density porous network at high solute concentrations, and a high-density compact network at low solute concentrations. This intriguing inverse concentration dependent self-assembly behavior has been attributed to the preaggregation of solute molecules in the heptanoic acid solution as revealed by UV-vis spectroscopy. The observed results have been correlated to the molecular density of self-assembled monolayers attained at the HA/HOPG interface.

| S-EPMC8514005 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data