Unraveling the Interactions between Lithium and Twisted Graphene.

Graphene is undoubtedly the carbon allotrope that has attracted the attention of a myriad of researchers in the last decades more than any other. The interaction of external or intercalated Li and Li with graphene layers has been the subject of particular attention for its importance in the applications of graphene layers in Lithium Batteries (LiBs). It is well known that lithium atoms and Li can be found inside and/or outside the double layer of graphene, and the graphene layers are often twisted around its parallel plane to obtain twisted graphene with tuneable properties.

Porous Carbon Materials Obtained by the Hydrothermal Carbonization of Orange Juice.

Porous carbon materials are currently subjected to strong research efforts mainly due to their excellent performances in energy storage devices. A sustainable process to obtain them is hydrothermal carbonization (HTC), in which the decomposition of biomass precursors generates solid products called hydrochars, together with liquid and gaseous products. Hydrochars have a high C content and are rich with oxygen-containing functional groups, which is important for subsequent activation.

Cresyl Violet Adsorption on Sonicated Graphite Oxide.

We present a study of adsorption of Cresyl Violet (CV) in aqueous solution on sonicated Graphite Oxide (sGO). For comparison, we also show adsorption results of Methylene Blue (MB) and Acridine Orange (AO) performed in the same conditions. The adsorbent was synthesized by the Tour's method followed by washing in water and ethanol and sonication, without any reduction, and studied by Raman, IR, UV-Vis, SEM and TEM techniques.

Bromide ion exchange with a Keggin polyoxometalate on functionalized polymeric membranes: a theoretical and experimental study.

Noncovalent interactions between the polyoxometalate [PMo12O40](3-) and acryloyloxyundecyltrimethyl ammonium bromide surfactant, used during membrane preparation, were evaluated in the frame of density functional theory. The electronic solvation energy of [PMo12O40](3) and bromide anions was also evaluated, at the same level of theory, in order to predict a probable exchange on the polymeric surface between these anions at the water/polymer interface. Energy balances were theoretically assessed, showing that the bromide cannot be exchanged with this nanosized polyanion in large extent.

On the cause of controlling affinity to small molecules of imprinted polymeric membranes prepared by noncovalent approach: a computational and experimental investigation.

Imprinting technique applied to membrane preparation via phase inversion methods yields membranes with enhanced affinity toward target molecules. In the imprinted membranes prepared by noncovalent approach hydrogen bond and electrostatic interactions can play a crucial role in determining the performance of these membranes. In this work, quantum mechanical calculations and experiments were performed to understand the physical-chemical causes of the affinity increase in imprinted polymeric membranes to 4,4'-methylendianiline (MDA), dissolved in an organic solvent.

Competitive hydrogen-bonding interactions in modified polymer membranes: a density functional theory investigation.

The subject of this work is the density functional theory (DFT) investigation of competitive hydrogen-bonding interactions that occur in modified block poly(ether/amide) (PEBAX) membranes. Previously, an evaluation of hydrogen-bonding interactions occurring between N-ethyl-o,p-toluensulfonamide (KET) modifiers was performed to establish the role of these interactions in affinity processes when the modifier is dissolved in PEBAX matrixes. However, some issues related to polymer-polymer (host-host) and modifier-polymer (host-guest) interactions were not analyzed from a theoretical point of view in the previous analysis.

New PVDF membranes: The effect of plasma surface modification on retention in nanofiltration of aqueous solution containing organic compounds.

New nanofiltration membranes were prepared by non-solvent-induced phase inversion from a PVDF/DMF/water system. The effect of exposure time before coagulation on the membrane characteristics (morphology, thickness, overall porosity, tensile strength) was investigated. PVDF membrane prepared at a fixed exposure time of 45s (PF45) was further plasma surface modified (RF 13.

Intermolecular interactions as controlling factor for water sorption into polymer membranes.

A multidisciplinary approach was used for delineating the mechanisms controlling water sorption into modified block co-poly-(ether/amide) (PEBAX) membranes. In particular, incorporation of aromatic sulfonamide (KET) into the polymer matrix led to a nonlinear increase of water sorption in the membrane. The modification in sorption was accompanied by a nonlinear behavior in membrane surface energies.

Membrane contactors in the beverage industry for controlling the water gas composition.

In the work described here, membrane contactors are used for coupling the removal of species (oxygen and hydrogen sulfide) present in the water with the water carbonation process. We include both experiments and a theoretical study devoted to the analysis of the transport phenomena that occur in the membrane contactor. The main resistance to mass transport was located at the liquid side.