A.R. Rodríguez-Domínguez

Bio: A.R. Rodríguez-Domínguez is an academic researcher from Universidad Autónoma de San Luis Potosí. The author has contributed to research in topics: Cluster (physics) & Density functional theory. The author has an hindex of 8, co-authored 18 publications receiving 151 citations.

Stability of Ni Clusters and the Adsorption of CH4: First-Principles Calculations

Abstract: Structural, magnetic and adsorption properties of Nin (n = 2–16, 21, 55) clusters have been investigated based on density funciontal theory (DFT) with the spin polarized generalized gradient approximation, using the Perdew–Burke–Ernzerhof functional. The most stable isomers have been selected to study the adsorption of methane CH4 and methyl CH3. It is found that the CH4 molecule adsorbs on the top site for all clusters considered. The most selective Nin clusters are the tetrahedron (n = 4) and icosahedral clusters due to high-coordinated edge atoms (n = 13, 21, and 55). For CH3, stronger adsorption tendencies were found with similar patterns. Our results show that clusters with n = 6, 10, and 13 with complete atomic shells are relatively more stable. Besides, they perform the lowest adsorption for CH3, indicating that they possess such a desirable property of a higher carbon poisoning resistance, than for the rest of the clusters. This result can be understood in terms of the electronic stability and loc...

Size and structure effects of PtN (N = 12 − 13) clusters for the oxygen reduction reaction: First-principles calculations

Abstract: Size and structure effects on the oxygen reduction reaction on PtN clusters with N = 12-13 atoms have been investigated using periodic density functional theory calculations with the generalized gradient approximation. To describe the catalytic activity, we calculated the O and OH adsorption energies on the cluster surface. The oxygen binding on the 3-fold hollow sites on stable Pt12-13 cluster models resulted more favorable for the reaction with O, compared with the Pt13(Ih) and Pt55(Ih) icosahedral particles, in which O binds strongly. However, the rate-limiting step resulted in the removal of the OH species due to strong adsorptions on the vertex sites, reducing the utility of the catalyst surface. On the other hand, the active sites of Pt12-13 clusters have been localized on the edge sites. In particular, the OH adsorption on a bilayer Pt12 cluster is the closest to the optimal target; with 0.0-0.2 eV weaker than the Pt(111) surface. However, more progress is necessary to activate the vertex sites of the clusters. The d-band center of PtN clusters shows that the structural dependence plays a decisive factor in the cluster reactivity.

Hydrogen Chemisorption on Pd-Doped Copper Clusters

Abstract: The structural evolution, electronic, and magnetic properties of Pd-doped Cun (n = 1–12) clusters and the dissociative chemisorption of H2 on the lowest energy structures are investigated on the ba...

Structures and Electronic Properties of TinV (n = 1–16) Clusters: First-Principles Calculations

Abstract: Structures and electronic properties of TinV (n = 1–16) clusters have been investigated using density functional theory with the generalized gradient approximatio. The calculations have shown that the TinV clusters favor compact spherical structures having similar conformations to the pure Tin clusters. The results show that the vanadium atom remains on the surface when n ⩽ 8 and n = 16, while for n = 9–15, it occupies the endohedral position. The Ti6V, Ti12V, and Ti14V clusters are found to be more stable than their neighbors, consistent with pure Tin clusters that have the same size. Additionally Ti4V has been found to be also magic, consistent with recent reports of B- and Al-doped Ti clusters. Small TinV (n ⩽ 4) clusters exhibit a transition from metallic-like to semimetallic electronic structure, while for n = 5 onward, no significant changes are observed compared with pure Tin clusters.

Electrocatalysis on Platinum Nanoparticles: Particle Size Effect on Oxygen Reduction Reaction Activity

Abstract: We determined the size-dependent specific and mass activities of the oxygen reduction in HClO(4) solutions on the Pt particles in the range of 1-5 nm. The maximal mass activity at 2.2 nm is well explained based on density functional theory calculations performed on fully relaxed nanoparticles. The presence of the edge sites is the main reason for the low specific activity in nanoparticles due to very strong oxygen binding energies at these sites. Our results clearly demonstrate that the catalytic activity highly depends on the shape and size of the nanoparticles.

Charge-controlled switchable CO2 capture on boron nitride nanomaterials

Abstract: Increasing concerns about the atmospheric CO2 concentration and its impact on the environment are motivating researchers to discover new materials and technologies for efficient CO2 capture and conversion. Here, we report a study of the adsorption of CO2, CH4, and H2 on boron nitride (BN) nanosheets and nanotubes (NTs) with different charge states. The results show that the process of CO2 capture/release can be simply controlled by switching on/off the charges carried by BN nanomaterials. CO2 molecules form weak interactions with uncharged BN nanomaterials and are weakly adsorbed. When extra electrons are introduced to these nanomaterials (i.e., when they are negatively charged), CO2 molecules become tightly bound and strongly adsorbed. Once the electrons are removed, CO2 molecules spontaneously desorb from BN absorbents. In addition, these negatively charged BN nanosorbents show high selectivity for separating CO2 from its mixtures with CH4 and/or H2. Our study demonstrates that BN nanomaterials are excellent absorbents for controllable, highly selective, and reversible capture and release of CO2. In addition, the charge density applied in this study is of the order of 1013 cm–2 of BN nanomaterials and can be easily realized experimentally.

New Horizon of Nanoparticle and Cluster Catalysis with Dendrimers

Abstract: Among various approaches synthesizing metal nanoparticles and tiny clusters, a template method using dendrimers has significant advantages over other chemical approaches with respect to their synthetic precision and the scalability. A dendrimer of polydentate ligands assembles metal ions or salts into the interior allowing production of metal nanoparticles in the dendrimer. The dendrimer-encapsulated nanoparticles (DENs) exhibit unique and remarkable catalytic properties depending on the size and elemental formula. Recent advances in dendrimer chemistry even enabled the atom precise synthesis of subnanometer metal clusters that have been impossible to prepare by wet chemical methods. In addition, not only for the synthesis of metal nanoparticles and clusters, the dendrimer itself can also provide the modulation of activity and selectivity in the catalysis. In this review, we summarized the most relevant research in which the dendrimer was employed as the template, modulator, or stabilizer for nanoparticle synthesis for catalytic applications.

Endohedrally Doped Cage Clusters

Abstract: The discovery of carbon fullerene cages and their solids opened a new avenue to build materials from stable cage clusters as “artificial atoms” or “superatoms” instead of atoms. However, cage clust...

Accelerating Chemo- and Regioselective Hydrogenationof Alkynes over Bimetallic Nanoparticles in a Metal–OrganicFramework

Abstract: Selective semihydrogenation of alkynes has been a long-term and significant target, yet it remains a great challenge. Herein, bimetallic nanoparticles in a metal–organic framework (MOF), i.e., CuPd...