Pd<sub>1</sub>/BN as a promising single atom catalyst of CO oxidation: a dispersion-corrected density functional theory study

Lu, Zhansheng; Lv, Peng; Xue, Jie; Wang, Huanhuan; Wang, Yizhe; Huang, Yue; He, Chaozheng; Ma, Dongwei; Yang, Zongxian

doi:10.1039/c5ra14057a

Cited by 70 publications

(45 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…32,61 Moreover, a previous study has shown that the HOMO of the CO molecule (5s) has weight mainly around the C atom, 62 indicating that CO always acts as a donor when its C end points to the anchoring atom. The current phenomenon is similar to the positively charged CO over Al/graphene, 28 Pd/BN 56 and Pt/BNNT. 63 Both the 5s and 1p orbitals of CO hybridize with the Ag-4d states in the energy range from À8 eV to À6 eV, and the two Ag-4d peaks near the Fermi level also overlap with the 2p* orbitals of CO, confirming the strong interaction between Ag and CO.…”

Section: Adsorption Of Species Involved In the Co Oxidation Over Ag 1supporting

confidence: 50%

A promising single atom catalyst for CO oxidation: Ag on boron vacancies of h-BN sheets

Yang

et al. 2017

Phys. Chem. Chem. Phys.

Self Cite

103

View full text Add to dashboard Cite

Single atom catalysts (SACs) have attracted broad research interest in recent years due to their importance in various fields, such as environmental protection and energy conversion. Here, we discuss the mechanisms of CO oxidation to CO 2 over single Ag atoms supported on hexagonal boron-nitride sheets (Ag 1 /BN) through systematic van der Waals inclusive density functional theory (DFT-D)calculations. The Ag adatom can be anchored onto a boron defect (V B ), as suggested by the large energy barrier of 3.12 eV for Ag diffusion away from the V B site. Three possible mechanisms (i.e., Eley-Rideal, Langmuir-Hinshelwood, and termolecular Eley-Rideal) of CO oxidation over Ag 1 /BN are investigated. Due to ''CO-Promoted O 2 Activation'', the termolecular Eley-Rideal (TER) mechanism is the most relevant one for CO oxidation over Ag 1 /BN and the rate-limiting reaction barrier is only 0.33 eV. More importantly, the first principles molecular dynamics simulations confirm that CO oxidation via the TER mechanism may easily occur at room temperature. Analyses with the inclusion of temperature and entropy effects further indicate that the CO oxidation via the TER mechanism over Ag 1 /BN is thermodynamically favorable in a broad range of temperatures.

show abstract

Section: Adsorption Of Species Involved In the Co Oxidation Over Ag 1supporting

confidence: 50%

A promising single atom catalyst for CO oxidation: Ag on boron vacancies of h-BN sheets

Yang

et al. 2017

Phys. Chem. Chem. Phys.

Self Cite

103

View full text Add to dashboard Cite

show abstract

“…Coordinative species around the metal atoms have been demonstrated to participate in the activation/stabilization of substrates or intermediates in some reactions . While the Mars–Van Krevelen mechanism was often proposed for CO oxidation on oxide‐supported atomically dispersed metal catalysts, the Langmuir–Hinshelwood mechanism and the Eley–Rideal mechanism were more plausible for single‐metal‐atom catalysts on supports without metals, such as BN . In some reactions, the distinct coordinative environment and electronic structure of atomically dispersed metal atoms on these supports make them superior to their oxide‐supported counterparts.…”

Section: Atomically Dispersed Metal Catalysts On Metal‐free Supportsmentioning

confidence: 99%

Strategies for Stabilizing Atomically Dispersed Metal Catalysts

et al. 2017

View full text Add to dashboard Cite

usually consist of ill-defined catalytic sites such that the reaction may undergo different catalytic pathways at different sites with different structural features. [2] The catalytic performance of a typical supported metal catalyst depends on numerous parameters, such as the composition, size, and shape of the metal nanoparticles, the nature of the supports, and the metal-support interactions, making it highly challenging to identify the catalytic site and thus simultaneously achieve high activity and high selectivity. [3] That is to say, conventional heterogeneous metal catalysts are still far away from the requirement of green chemistry, in which the reaction selectivity is crucial. Atomically dispersed metal catalysts have attracted more and more attention as they have maximal atomic utilization as well as uniform coordination environments, thus providing an ideal model for mechanistic investigation. [4] However, isolated metal atoms have extremely high surface energy so that they tend to aggregate to form nanoparticles, especially under harsh preparation or catalysis conditions. [5] During the past decades, several strategies have been developed to stabilize single-site metal catalysts on various supports. As shown in Figure 1, anchoring organometallic catalysts onto the surface of supports through organic linkers or weak interactions (e.g., hydrogen bonds and electrostatic interactions) and encapsulating organometallics in the micropores of the support represent two early approaches to immobilize singleatom metal catalysts and thus enhance their stabilities for catalysis. The metal centers of the catalysts prepared by these two methods do not have direct interactions with supports. The knowledge learned from homogeneous catalysts can be easily migrated into heterogeneous systems. Since there have been already nice review articles on heterogenized organometallic catalysts, [6] these early-studied catalysts are not included in the scope here. Readers should also refer to some excellent reviews in the literature for a more comprehensive view on atomically dispersed metal catalysts. [7] Here, we mainly discuss how to stabilize single metal atoms on supports through direct chemical interactions and focus on the following three different classes of atomically dispersed catalysts:Metal centers in this class of catalysts are co-stabilized by both supports and organic ligands. To prepare this type of catalysts, mononuclear organometallic catalysts with labile ligands are usually used as precursors to allow the direct deposition of catalytic metal atoms onto oxide supports through metal-oxygen interactions. The easy reaction between the labile ligands on the organometallic precursors and the Atomically dispersing metal atoms on supports provides an ideal strategy for maximizing metal utilization for catalysis, which is particularly important for fabricating cost-effective catalysts based on Earth-scarce metals. However, due to the high surface energy and thus instability of single atoms, it remains challenging ...

show abstract

“…We found a barrier of 5.5 eV from IS to hollow site 1, and 6.3 eV from IS to hollow site 2. These barriers were larger than the 3.8 and 5.3 eV barriers for the Pd-BN sheet [35]. Our results showed that, under normal conditions, Ni atoms would not diffuse significantly away from the B-vacancy sites, leading to good stability.…”

Section: Geometry and Stabilitymentioning

confidence: 61%

“…A new three-molecule process was recently reported for single Au catalytic sites in h-BN [30]. After that, the TER process for CO oxidation was also found to occur on single Co [32] and Pd [35] catalytic sites in h-BN. Reaction energies for the TER process for Ni are shown in Figure 7.…”

Section: Ter Processmentioning

confidence: 89%

See 1 more Smart Citation

First-Principles Investigations of Single Metal Atoms (Sc, Ti, V, Cr, Mn, and Ni) Embedded in Hexagonal Boron Nitride Nanosheets for the Catalysis of CO Oxidation

2019

View full text Add to dashboard Cite

We evaluated isolated transition metal atoms (Sc, Ti, V, Cr, Mn, and Ni) embedded in hexagonal-BN as novel single atom catalysts for CO oxidation. We predicted that embedded Ni atoms should have superior performance for this task. Ti, V, and Mn bind CO2 too strongly and so the reaction will not proceed smoothly. We studied the detailed reaction processes for Sc, Cr, and Ni. The Langmuir–Hinshelwood (LH), Eley–Rideal (ER), and the new termolecular Eley–Rideal (TER) processes for CO oxidation were investigated. Sc was not effective. Cr primarily used the ER process, although the barrier was relatively large at 1.30 eV. Ni was the best of the group, with a 0.44 eV barrier for LH, and a 0.47 eV barrier for TER. Therefore, we predicted that the LH and TER processes could operate at relatively low temperatures between 300 and 500 K.

show abstract

Pd₁/BN as a promising single atom catalyst of CO oxidation: a dispersion-corrected density functional theory study

Cited by 70 publications

References 34 publications

A promising single atom catalyst for CO oxidation: Ag on boron vacancies of h-BN sheets

A promising single atom catalyst for CO oxidation: Ag on boron vacancies of h-BN sheets

Strategies for Stabilizing Atomically Dispersed Metal Catalysts

First-Principles Investigations of Single Metal Atoms (Sc, Ti, V, Cr, Mn, and Ni) Embedded in Hexagonal Boron Nitride Nanosheets for the Catalysis of CO Oxidation

Contact Info

Product

Resources

About

Pd1/BN as a promising single atom catalyst of CO oxidation: a dispersion-corrected density functional theory study

Cited by 70 publications

References 34 publications

A promising single atom catalyst for CO oxidation: Ag on boron vacancies of h-BN sheets

A promising single atom catalyst for CO oxidation: Ag on boron vacancies of h-BN sheets

Strategies for Stabilizing Atomically Dispersed Metal Catalysts

First-Principles Investigations of Single Metal Atoms (Sc, Ti, V, Cr, Mn, and Ni) Embedded in Hexagonal Boron Nitride Nanosheets for the Catalysis of CO Oxidation

Contact Info

Product

Resources

About

Pd₁/BN as a promising single atom catalyst of CO oxidation: a dispersion-corrected density functional theory study