A B S T R C : study of the ion-exchange properties montmorillonite has been performed in order to facilitate computer predictions chemical natural fluids and mineral assemblies. Clay/electrolyte interactions can be described using a technique based on concept hypothetical surface complex formation. This technique, which is compatible with ion-association models such as GEOCHEM, used simulate simultaneous ionexchange, hydrolysis clay edges anion adsorption surfaces. Effects variable...

Graphitic carbon nitride (g-C3N4) is known to photogenerate hydrogen peroxide in the presence of hole quenchers aqueous environments. Here, g-C3N4 photocatalyst embedded into a host polymer intrinsic microporosity (PIM-1) provide recoverable heterogenized photocatalysts without loss activity. Different types (including Pt@g-C3N4, Pd@g-C3N4, and Au@g-C3N4) different are investigated. Exploratory experiments yield data that suggest binding quencher either (i) directly by adsorption onto (as...

Molecular recognition and sensing can be coupled to interfacial capacitance changes on graphene foam surfaces linked double layer effects enhanced quantum capacitance. 3D film electrodes (Gii-Sens; thickness approximately 40 μm; roughness factor 100) immersed in aqueous buffer media exhibit an order of magnitude jump electrochemical upon adsorption a charged molecular receptor based pyrene-appended boronic acids (here, 4-borono-1-(pyren-2-ylmethyl)pyridin-1-ium bromide, or abbreviated T1)....

This study examines the role of defects in structure–property relationships spinel LiMn1.5Ni0.5O4 (LMNO) cathode materials, especially terms Mn3+ content, degree disorder, and impurity phase, without use traditional high-temperature annealing (≥700 °C used for making disordered LMNO). Two different phases LMNO (i.e., highly P4332-ordered Fd3̅m-disordered) have been prepared from two β-MnO2−δ precursors obtained an argon-rich atmosphere (β-MnO2−δ (Ar)) a hydrogen-rich [β-MnO2−δ (H2)]. The...

Abstract The binary cation exchange processes, Na → Ca, Mg, and Ca were investigated at 298 K for a montmorillonitic soil separate (principally clay silt) suspended in 50 mol m −3 perchlorate background pH 6, 6.6, or 7. resulting isotherms indicated some preference on the Mg over Na, Mg. These preferences attributed primarily to organic matter associated with separate, since previous studies had shown that pure montmorillonite exhibits essentially no among three cations under same conditions...

As part of a general study the theory ternary ion exchange in zeolites, simple model is developed for evaluation required activity-coefficient ratios dilute solutions containing three salts. The application this discussed with particular reference to or multicomponent zeolites.

Electrosynthesis traditionally requires dedicated reactor systems and an added electrolyte, although some paired electrosynthesis processes are possible at interdigitated microband electrodes simply immersed in solution without intentionally electrolyte. Here, 1,1′-ferrocenedimethanol oxidation activated olefin electro-hydrogenation reactions investigated as model a Pt–Pt array electrode with 5 μm width interelectrode gap. Voltammetric responses for discussed, product yields determined...

The triphasic interaction of gases with electrode surfaces immersed in aqueous electrolyte is crucial electrochemical technologies (fuel cells, batteries, sensors). Some microporous materials modify this locally via storage capacity for environments linked to changes apparent oxygen concentration and diffusivity (as well as activity reactivity). Here, a nanoparticulate polymer intrinsic microporosity (PIM-1) shown store gas thereby enhance signals reduction media. Oxygen current transient...

The interfacial capacitance of graphene foam electrodes (Gii-Sens) in contact to aqueous media (determined by electrochemical impedance spectroscopy) is strongly affected adsorption 1-pyrenemethylamine (PMA). An order magnitude increase upon ascribed predominantly the quantum contribution (i.e. changes electronic density states layers) response cationic adsorbent. A change (reversible) observed as a function pH. Although likely be linked amine protonation, measured occurs over wide range pH...

Ion-exchange isotherms for the Na ⇌ NH4 equilibrium in zeolites X and Y were constructed at 298 K a total solution normality of 0.1 g-equiv. dm–3. Values standard free energy exchange calculated shown to be consistent with affinity sequence predicted using dielectric theory. Comparisons are made between previously reported studies on this current work, differences experimental data discussed. Statistical thermodynamic considerations provide greater understanding Y, collectively evidence...

The ion-exchange properties of hydrated and amminated silver(I) ions in synthetic sodium X Y zeolites mordenite (MOR) were examined at 25 °C a total solution normality 0.1 g equiv dm–3. Ion exchange isotherms constructed for each system thermodynamic affinity sequence ≫ > MOR was found the Ag(aq)⇌ Na equilibria. In contrast, selectivity observed Ag(NH3)2⇌ These sequences are rationalised using simple dielectric theory or, cases involving silver ion, modification theory.

Graphitic carbon nitride with photo-attached platinum nanoparticles of typically 2.5 nm diameter, [email protected]3N4, is known for photo-generation hydrogen in aqueous environments and the presence hole quenchers. Here, generation photocurrents from photo‑hydrogen production observed at a electrode, driven by oxalate or glucose quenchers, enhanced polymer intrinsic microporosity PIM-1 coated over protected]3N4 deposit. The ability to create triphasic conditions capture leads photocurrent...

The concept of a reversible polymer displacement sensor mechanism for electrochemical glucose monitoring is demonstrated. A pyrene-derivatised boronic acid chemo-receptor adsorbed onto graphene foam electrode. Spontaneous oxidative polymerisation nordihydroguaiaretic (NHG) the electrode leads to redox active film (poly-NHG) covalently attached receptors. Oxidation poly-NHG frees receptors interact with from solution phase, which detected due competitive binding when reduced re-binds...

Molecularly rigid polymers with internal charges (positive induced by amine methylation) allow electroosmotic water flow to be tuned adjusting the charge density (the degree of methylation). Here, a microporous polyamine (PIM-EA-TB) is methylated give molecularly anion conductor. The drag coefficient number molecules transported per anion) shown increase lower methylation. Net transport (without flow) in coupled anionic diode circuit demonstrated based on combining low and high materials....

As a route to the formation of regular arrays AlN nanorods, in contrast other III-V materials, use selective area growth via metal organic vapor phase epitaxy (MOVPE) has so far not been successful. Therefore, this work we report fabrication highly uniform and ordered nanorod scaffold using an alternative hybrid top-down etching bottom-up regrowth approach. The nanorods are created across full 2-inch template by combining Displacement Talbot Lithography lift-off create Ni nanodot mask,...

Ion-exchange characteristics have been determined for the binary exchanges of Cd2+ and Ca2+ in sodium X zeolite using a variety anionic backgrounds. A thermodynamic model, previously presented evaluation activity coefficients salts mixed electrolyte solutions, is applied to calculate data these exchanges. The application this model shows that changes cadmium selectivity as function changing background can be rationalised entirely terms magnitude solution-phase coefficients.The reversibility...

Abstract A film of the polymer intrinsic microporosity PIM‐7 is coated onto a glassy carbon electrode and resulting effects on electron transfer reactions are studied for three different types processes: (i) aqueous solution based, (ii) solid state surface immobilised, (iii) electrocatalytic processes electrodeposited palladium. The reactivity hydroquinone oxidation in phosphate buffer shown to be linked causing slightly lower rate mass transport without detrimental reaction kinetics. Next,...

Abstract An indirect fuel cell concept is presented herein, where a palladium‐based membrane (either pure Pd with 25 μm thickness or 75 Ag alloy 10 thickness) used to separate the electrochemical compartment from catalysis compartment. In this system, hydrogen generated hydrogen‐rich molecule, such as formic acid, and selectively permeated through into it then converted electricity. way, in situ, overcoming issues associated storage presenting chemical an attractive feasible alternative...