2016 |
Miranda-Rojas, S; Salazar-Molina, R; Kastner, J; Arratia-Perez, R; Mendizabal, F Theoretical Exploration of Seleno and Tellurophenols as Promising Alternatives to Sulfur Ligands for Anchoring to Gold (111) Materials Artículo de revista Rsc Advances, 6 (6), pp. 4458-4468, 2016, ISSN: 2046-2069. Resumen | Enlaces | BibTeX | Etiquetas: basis-sets, chain-length, charge-transfer, chemistry, complexes, interface, monolayers, nanoparticles, pseudopotentials, self-assembled tellurium titanium @article{RN306, title = {Theoretical Exploration of Seleno and Tellurophenols as Promising Alternatives to Sulfur Ligands for Anchoring to Gold (111) Materials}, author = { S. Miranda-Rojas and R. Salazar-Molina and J. Kastner and R. Arratia-Perez and F. Mendizabal}, url = {/brokenurl#<Go to ISI>://WOS:000369510500023}, doi = {10.1039/c5ra21964g}, issn = {2046-2069}, year = {2016}, date = {2016-01-01}, journal = {Rsc Advances}, volume = {6}, number = {6}, pages = {4458-4468}, abstract = {It is widely known that sulfur ligands, such as alkanethiols or phenothiols and their derivatives, are useful anchor systems for gold materials due to the high affinity of sulfur to gold surfaces. In this study we use DFT calculations and a 42-atom gold cluster model to study the interaction between selenophenol and tellurophenol-derivatives with the Au(111) surface to gain information towards potential new gold-based materials. We modulated the interaction strength by controlling the charge transfer process of a particular interaction by chemically modifying the ligands. To obtain a complete analysis, we studied the ligands in their protonated, anionic and radical states aiming to cover the three possibilities in which these may interact with the gold cluster. In order to get a deeper insight into the nature of the interaction we used several analysis techniques such as energy decomposition analysis (EDA), non-covalent interactions (NCI) and natural population analysis (NPA). Our results reveal that tellurium in the anionic state provides complexes of better thermodynamic stability by similar to 12.0 kcal mol, when compared with the strongest sulfur-gold complex, also in the anionic state. Furthermore, this indicates that the anionic ligand is probably the dominant state for both selenium and tellurium as observed previously for sulfur. The extent to which the interaction strength could be controlled directly depends on the state of the anchor atom. In our case the anionic state is the most suitable for tuning the interaction. Finally, our main findings suggest that exchanging sulfur with selenium or tellurium involves an important increase of the interaction strength, thus, making these selenophenol and tellurophenol derivatives attractive for the development of new functional materials.}, keywords = {basis-sets, chain-length, charge-transfer, chemistry, complexes, interface, monolayers, nanoparticles, pseudopotentials, self-assembled tellurium titanium}, pubstate = {published}, tppubtype = {article} } It is widely known that sulfur ligands, such as alkanethiols or phenothiols and their derivatives, are useful anchor systems for gold materials due to the high affinity of sulfur to gold surfaces. In this study we use DFT calculations and a 42-atom gold cluster model to study the interaction between selenophenol and tellurophenol-derivatives with the Au(111) surface to gain information towards potential new gold-based materials. We modulated the interaction strength by controlling the charge transfer process of a particular interaction by chemically modifying the ligands. To obtain a complete analysis, we studied the ligands in their protonated, anionic and radical states aiming to cover the three possibilities in which these may interact with the gold cluster. In order to get a deeper insight into the nature of the interaction we used several analysis techniques such as energy decomposition analysis (EDA), non-covalent interactions (NCI) and natural population analysis (NPA). Our results reveal that tellurium in the anionic state provides complexes of better thermodynamic stability by similar to 12.0 kcal mol, when compared with the strongest sulfur-gold complex, also in the anionic state. Furthermore, this indicates that the anionic ligand is probably the dominant state for both selenium and tellurium as observed previously for sulfur. The extent to which the interaction strength could be controlled directly depends on the state of the anchor atom. In our case the anionic state is the most suitable for tuning the interaction. Finally, our main findings suggest that exchanging sulfur with selenium or tellurium involves an important increase of the interaction strength, thus, making these selenophenol and tellurophenol derivatives attractive for the development of new functional materials. |
Munoz-Castro, A; Gomez, T; Carey, D M; Miranda-Rojas, S; Mendizabal, F; Zagal, J H; Arratia-Perez, R Surface on Surface. Survey of the Monolayer Gold-Graphene Interaction from Au-12 and Pah Via Relativistic Dft Calculations Artículo de revista Journal of Physical Chemistry C, 120 (13), pp. 7358-7364, 2016, ISSN: 1932-7447. Resumen | Enlaces | BibTeX | Etiquetas: ab-initio, approximation, chemistry clusters, density-functional generalized gradient hydrogen-bonds, interaction, monolayers, noncovalent phthalocyanines, pseudopotentials, self-assembled theory @article{RN303, title = {Surface on Surface. Survey of the Monolayer Gold-Graphene Interaction from Au-12 and Pah Via Relativistic Dft Calculations}, author = { A. Munoz-Castro and T. Gomez and D.M. Carey and S. Miranda-Rojas and F. Mendizabal and J.H. Zagal and R. Arratia-Perez}, url = {/brokenurl#<Go to ISI>://WOS:000373862700049}, doi = {10.1021/acs.jpcc.5b12580}, issn = {1932-7447}, year = {2016}, date = {2016-01-01}, journal = {Journal of Physical Chemistry C}, volume = {120}, number = {13}, pages = {7358-7364}, abstract = {Gold-graphene interaction at the interface is evaluated through different polyaromatic hydrocarbons (PAH), accounted by C6H6, C24H12, C54H16, and C96H18, focusing into different energetic terms related to the overall interaction. Our results characterize the neutral gold-PAH interaction nature with 45% of dispersion character, 35% of electrostatic, and 20% of covalent character, suggesting that moderate van der Waals character is mostly involved in the interaction, which increases according to the size of the respective PAH. The resulting surface charge distribution in the graphene model is a relevant parameter to take into account, since the ability of the surface charge to be reorganized over the polycyclic structure in both contact and surrounding regions is important in order to evaluate interactions and different interacting conformations. Our results suggest that for a Au-12 contact surface of radius 4.13 angstrom, the covalent, electrostatic and dispersion character of the interaction are effectively accounted in a graphene surface of about 6.18 angstrom, as given by circumcoronene, depicting a critical size where the overall interaction character can be accounted.}, keywords = {ab-initio, approximation, chemistry clusters, density-functional generalized gradient hydrogen-bonds, interaction, monolayers, noncovalent phthalocyanines, pseudopotentials, self-assembled theory}, pubstate = {published}, tppubtype = {article} } Gold-graphene interaction at the interface is evaluated through different polyaromatic hydrocarbons (PAH), accounted by C6H6, C24H12, C54H16, and C96H18, focusing into different energetic terms related to the overall interaction. Our results characterize the neutral gold-PAH interaction nature with 45% of dispersion character, 35% of electrostatic, and 20% of covalent character, suggesting that moderate van der Waals character is mostly involved in the interaction, which increases according to the size of the respective PAH. The resulting surface charge distribution in the graphene model is a relevant parameter to take into account, since the ability of the surface charge to be reorganized over the polycyclic structure in both contact and surrounding regions is important in order to evaluate interactions and different interacting conformations. Our results suggest that for a Au-12 contact surface of radius 4.13 angstrom, the covalent, electrostatic and dispersion character of the interaction are effectively accounted in a graphene surface of about 6.18 angstrom, as given by circumcoronene, depicting a critical size where the overall interaction character can be accounted. |
Miranda-Rojas, S; Sierra-Rosales, P; Munoz-Castro, A; Arratia-Perez, R; Zagal, J H; Mendizabal, F Catalytic Aspects of Metallophthalocyanines Adsorbed on Gold-Electrode. Theoretical Exploration of the Binding Nature Role Artículo de revista Physical Chemistry Chemical Physics, 18 (42), pp. 29516-29525, 2016, ISSN: 1463-9076. Resumen | Enlaces | BibTeX | Etiquetas: complexes, fe iron-phthalocyanine, metal monolayers, oxidation phthalocyanines, pseudopotentials, scanning-tunneling-microscopy, self-assembled supramolecular surfaces @article{RN308, title = {Catalytic Aspects of Metallophthalocyanines Adsorbed on Gold-Electrode. Theoretical Exploration of the Binding Nature Role}, author = { S. Miranda-Rojas and P. Sierra-Rosales and A. Munoz-Castro and R. Arratia-Perez and J.H. Zagal and F. Mendizabal}, url = {/brokenurl#<Go to ISI>://WOS:000387024300053}, doi = {10.1039/c6cp06156g}, issn = {1463-9076}, year = {2016}, date = {2016-01-01}, journal = {Physical Chemistry Chemical Physics}, volume = {18}, number = {42}, pages = {29516-29525}, abstract = {The need of deeper insights regarding the inner working of catalysts represents a current challenge in the search of new ways to tune their activities towards new chemical transformations. Within this field, metallophthalocyanines-based (MPc) electrocatalysis has gained tremendous attention due to their versatility, low cost, great stability and excellent turn-over properties. In this concern, here we present a quantum chemical study of the formation of supramolecular complexes based on the adsorption of MPcs on gold substrates, and the effect of the substrate on their electrocatalytic properties. For this purpose, we used iron-(FePc), cobalt( CoPc) and copper-phthalocyanines (CuPc). To model the gold surface we used two gold clusters of different sizes, given by Au-26 and Au-58 accounting for gold electrode Au(111) surface. Thus, both electronic and binding strength features of the adsorption process between the complexes were analyzed in detail in order to gain a deeper description of the nature of the MPc-Au(111) formation, by using Density Functional Theory (DFT) calculations, at the PBE and TPSS levels including the dispersive contribution according to the Grimme approach (D3). Our results show that dispersion forces rule the MPc-gold interaction, with binding strengths ranging between 61 and 153 kcal mol(-1), in agreement to the reported experimental data. To provide a detailed picture of our findings we used the non-covalent interactions index (NCIs) analysis, which offers additional chemical insights regarding the forces that control their interaction strength. Finally, our calculations revealed that among the three MPcs, CuPc required less energy for its oxidation. However, the removal of the electron involves a tremendous decrease of the MPc-gold surface interaction strength thus suggesting its desorption, which would prevent the required reversibility of the redox reaction, explaining its low performance observed experimentally.}, keywords = {complexes, fe iron-phthalocyanine, metal monolayers, oxidation phthalocyanines, pseudopotentials, scanning-tunneling-microscopy, self-assembled supramolecular surfaces}, pubstate = {published}, tppubtype = {article} } The need of deeper insights regarding the inner working of catalysts represents a current challenge in the search of new ways to tune their activities towards new chemical transformations. Within this field, metallophthalocyanines-based (MPc) electrocatalysis has gained tremendous attention due to their versatility, low cost, great stability and excellent turn-over properties. In this concern, here we present a quantum chemical study of the formation of supramolecular complexes based on the adsorption of MPcs on gold substrates, and the effect of the substrate on their electrocatalytic properties. For this purpose, we used iron-(FePc), cobalt( CoPc) and copper-phthalocyanines (CuPc). To model the gold surface we used two gold clusters of different sizes, given by Au-26 and Au-58 accounting for gold electrode Au(111) surface. Thus, both electronic and binding strength features of the adsorption process between the complexes were analyzed in detail in order to gain a deeper description of the nature of the MPc-Au(111) formation, by using Density Functional Theory (DFT) calculations, at the PBE and TPSS levels including the dispersive contribution according to the Grimme approach (D3). Our results show that dispersion forces rule the MPc-gold interaction, with binding strengths ranging between 61 and 153 kcal mol(-1), in agreement to the reported experimental data. To provide a detailed picture of our findings we used the non-covalent interactions index (NCIs) analysis, which offers additional chemical insights regarding the forces that control their interaction strength. Finally, our calculations revealed that among the three MPcs, CuPc required less energy for its oxidation. However, the removal of the electron involves a tremendous decrease of the MPc-gold surface interaction strength thus suggesting its desorption, which would prevent the required reversibility of the redox reaction, explaining its low performance observed experimentally. |
2016 |
Theoretical Exploration of Seleno and Tellurophenols as Promising Alternatives to Sulfur Ligands for Anchoring to Gold (111) Materials Artículo de revista Rsc Advances, 6 (6), pp. 4458-4468, 2016, ISSN: 2046-2069. |
Surface on Surface. Survey of the Monolayer Gold-Graphene Interaction from Au-12 and Pah Via Relativistic Dft Calculations Artículo de revista Journal of Physical Chemistry C, 120 (13), pp. 7358-7364, 2016, ISSN: 1932-7447. |
Catalytic Aspects of Metallophthalocyanines Adsorbed on Gold-Electrode. Theoretical Exploration of the Binding Nature Role Artículo de revista Physical Chemistry Chemical Physics, 18 (42), pp. 29516-29525, 2016, ISSN: 1463-9076. |