First principles characterization of silicate sites in clay surfaces

Alvim, Raphael da Silva; Miranda, Caetano R.

doi:10.1039/c4cp05447d

Cited by 22 publications

(16 citation statements)

References 63 publications

(88 reference statements)

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“…Furthermore, the sample surface to be probed is a silicate sheet obtained from the exfoliation 5,75 of aluminosilicates like montmorillonite (MMT) clays in the surface (001). In our previous work, 7 we simulated the topographic NC-AFM image of the MMT surface using an implicit tip of silicon nitride. As described by Chan et al, 45 the force F ts was calculated by the first-principles potential with a fictitious tip.…”

Section: Resultsmentioning

confidence: 99%

“…Furthermore, vdW-DF is necessary to better describe the layered structure of the montmorillonite (MMT). 7 On the basis of our surface characterization work, 7 we showed the presence of two types of basal oxygen sites (O1 and O2 in Figure 1A) that may be differently affected by vdW forces and/or the chemical environment of the hydroxyl groups (O3 in Figure 1A). Although the structural hydroxyl groups O3 are in the siloxane cavity, surface characterization also brings out that the oxygen sites O1 and O2 are affected by those sites in a hydrophilic way.…”

Section: Computational Proceduresmentioning

confidence: 97%

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Noncontact AFM First-Principles Simulations of Functionalized Silicon Tips on the Montmorillonite (001) Surface

Alvim

Miranda

2016

J. Phys. Chem. C

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The interaction between functionalized silicon probe tips and the montmorillonite (MMT) surface was studied through density-functional theory (DFT) with the van der Waals DF (vdW-DF) to include the contribution of the vdW forces in the interaction energy of the tip/MMT interface. On the basis of the noncontact AFM (NC-AFM) technique, we modeled an explicit Si probe tip that was functionalized with sulfonic acid (SA) and ethylene glycol (EG) groups present in polymeric surfactants. Accordingly, we obtained the short-range microscopic forces to investigate the hysteresis mechanism due to the approach and retraction processes of the tips as well as tip tilt, usually leading to the topographic and dissipation image contrasts. Furthermore, it was possible assert the influence of different hydrophilicity degrees toward the oxygen sites at the silicate sheet of the MMT (001) surface, which is related to important processes of surface interaction. Our results showed both SA and EG hydrophilic functional groups are selective onto the two basal oxygen sites, which also take place in the interaction on the siloxane cavity in the MMT surface. In particular, on the basal oxygen site that interacts with the intralayer hydroxyl group, the EG tip leads to an energy dissipation due to different force pathways mainly in the repulsion region, while possible energy barriers can be overcome by approaching a larger tip tilt on the other basal oxygen site in the attraction region. This tip could then display less frequency shift on the basal oxygen sites of MMT. Therefore, our results can clarify important questions about the complexity of the interaction forces between functionalized silicon probe tips and MMT in the NC-AFM experiments. Moreover, this work provides a first-principles model to describe the hydrophilic selectivity of polymeric surfactants from the interaction between nonionic −OH groups and aluminosilicate surfaces in the absence of hydrophilic ions at the interlayer region.

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Section: Resultsmentioning

confidence: 99%

Section: Computational Proceduresmentioning

confidence: 97%

Noncontact AFM First-Principles Simulations of Functionalized Silicon Tips on the Montmorillonite (001) Surface

Alvim

Miranda

2016

J. Phys. Chem. C

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“…In particular, the distance-dependent measurement of tip/sample forces can reveal the chemical activity at the surface sites. This technique has also been employed to investigate the silicate surface properties and how the inner chemical environment can influence the outer atom due to the mineral hydroxyl groups and the ionic substitutions (Alvim and Miranda 2015). Such studies contributed to understanding how chemical additives can affect the interaction between the solid surface and the fluids phases, such as the organic functional groups in hydrocarbons in the oil, and the ions in the brine.…”

Section: Electronic Structure Levelmentioning

confidence: 99%

Multiscale Molecular Modeling Applied to the Upstream Oil & Gas Industry Challenges

et al. 2020

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This review brings an overview based on recent publications of multi-scale molecular modeling studies applied to the upstream Oil & Gas segment. These works provide suitable insights on technologies of Oil & Gas interest ranging from fluid properties under spatial confinement, and the phenomena occurring at brine-oil-rock interfaces through enhanced oil recovery processes. Within a broader phenomenological perspective, the subsurface phenomena may occur over distinct time and length scales. A suitable representation of the multiscale phenomena through molecular modeling may contribute to design optimized petrophysical processes from nano to macroscopic scales. This review covers several examples spanning from first principles calculations, molecular dynamics, mesoscopic modeling up to finite elements. At the electronic level, recent methodological advances and their corresponding implementations were essential to describe the energetics of fluid/rock interacting details accurately. Further, molecular dynamics simulations based on fully atomistic force fields taken from higher methodology resolutions, such as first principles calculations, were employed to characterize confinement interfaces, revealing the fluid structuring and interfacial properties, including the role of surfactant nanoparticles under reservoir conditions. These outputs served as modeling descriptors at mesoscale to simulate the oil displacement by fluid injection on pore network models. Finally, we discuss some perspectives and challenges, where multiscale approaches can provide suitable solutions by addressing other systems and properties of Oil & Gas industry interest. In light of multiscale molecular modeling, we propose its integration with reservoir simulators combined with machine learning techniques, and the design of nanostructured materials for further applications on the natural gas separation.

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“…It is worthy to note that whenever treating the vdW interactions the lattice lengths were slightly contracted compared to those obtained by LDA or GGA only. 2 Although it was found that the Al-Si model is slightly lower in energetics than the Al-Al model with ∼ 0.1 eV/cell energy difference, we will use these two models for further investigation of interlayer cation exchange to consider the different local environments around interlayer cation. Table 1 Optimized lattice parameters and unit cell volume V 0 of pre-exchanged muscovite models within LDA and GGA with and without DFT-D2 dispersion correction.…”

Section: Structural Propertiesmentioning

confidence: 99%

First-principles study of organically modified muscovite mica with ammonium (NH $$_4^+$$ 4 + ) or methylammonium (CH $$_3$$ 3 NH $$_3^+$$ 3 + ) ion

Choe

Jang

et al. 2016

J Mater Sci

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Using density functional theory calculations, we have investigated the interlayer cation exchange phenomena in muscovite mica, which is motivated by a necessity to develop flexible high-insulating covering materials. The crystalline structures, chemical bonding properties, energetics, and electronic properties of muscovites before and after exchange of interlayer K + cation with ammonium (NH + 4 ) or methylammonium (CH 3 NH + 3 ) ion were calculated. It was found that the unit cell volume changes are negligibly small upon exchange with NH + 4 ion, while the unit cells are expanded with about 4 % relative rate when replacing the interlayer K + cation with CH 3 NH + 3 ion. The energy band gap of pre-exchanged muscovite was calculated to be about 5 eV, which hardly changes upon interlayer cation exchange with either NH + 4 or CH 3 NH + 3 ion, indicating the preservation of high insulating property of muscovite. The exchange energies were found to be about -100 kJ/mol for NH + 4 and about -50 kJ/mol for CH 3 NH + 3 exchange, indicating that the exchange reactions are exothermic. A detailed analysis of atomic resolved den-Korea sity of states and electron density redistribution was provided.

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First principles characterization of silicate sites in clay surfaces

Cited by 22 publications

References 63 publications

Noncontact AFM First-Principles Simulations of Functionalized Silicon Tips on the Montmorillonite (001) Surface

Noncontact AFM First-Principles Simulations of Functionalized Silicon Tips on the Montmorillonite (001) Surface

Multiscale Molecular Modeling Applied to the Upstream Oil & Gas Industry Challenges

First-principles study of organically modified muscovite mica with ammonium (NH $$_4^+$$ 4 + ) or methylammonium (CH $$_3$$ 3 NH $$_3^+$$ 3 + ) ion

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