Si-doped C3N monolayers as efficient single-atom catalysts for the reduction of N2O: a computational study

Generating clean and sustainable hydrogen from water splitting processes represent a practical alternative to solve the energy crisis. Ultrathin two-dimensional materials exhibit attractive properties as catalysts for hydrogen production owing to their large surface-to-volume ratios and effective chemisorption sites. However, the catalytically inactive surfaces of the transition metal dichalcogenides (TMD) possess merely small areas of active chemical sites on the edge, thus decreasing their possibilities for practical applications. Here, we propose a new class of out-of-plane deformed TMD (cTMD) monolayer to anchor transition metal atoms for the activation of the inert surface. The calculated adsorption energy of metals (e.g., Pt) on curved MoS2 (cMoS2) can be greatly decreased by 72% via adding external compressions, compared to the basal plane. The enlarged diffusion barrier energy indicates that cMoS2 with an enhanced fixation of metals could be a potential candidate as a single atom catalyst (SAC). We made a well-rounded assessment of the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), which are two key processes in water splitting. The optimized Gibbs free energy of 0.02 for HER and low overpotential of 0.40 V for OER can be achieved when the proper compression and supported metals are selected. Our computational results provide inspiration and guidance towards the experimental design of TMD-based SACs.

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Are All Single Atoms Created Equal? Surface Density Dependent Catalytic Activity of Single Pd Atoms Supported on Ceria

10.26434/chemrxiv.14312780 ◽

2021 ◽

Author(s):

Yongseon Kim ◽

Gregory Collinge ◽

Mal Soon Lee ◽

Konstantin Khivantsev ◽

Sung June Cho ◽

...

Keyword(s):

Catalytic Activity ◽

Surface Density ◽

Reaction Rate ◽

Specific Activity ◽

Computational Study ◽

Single Atom ◽

Cooperative Effects ◽

Metal Atoms ◽

Specific Catalytic Activity ◽

Molecular Catalysts

The analogy between single atom catalysts (SACs) and molecular catalysts predicts that the specific catalytic activity of these systems is constant. We provide evidence that this prediction is not necessarily true. As a case in point, we show that the specific activity over ceria5 supported single Pd atoms linearly increases with metal atom density, originating from the cumulative enhancement of lattice oxygen mobility. The long-range electrostatic fingerprints (~1.5 nm) around each Pd site overlap with each other as surface Pd density increases, resulting in the observed deviation from constant specific activity. These cooperative effects exhaust previously active O atoms above a certain Pd density, leading to their permanent 10 removal and consequent drop in reaction rate. The findings of our combined experimental and computational study show that the specific catalytic activity of reducible oxide-supported single atom catalysts can be tuned by varying the surface density of single metal atoms.

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Hydrogen fluoride on the pristine, Al and Si doped BC2N nanotubes: A computational study

Computational Materials Science ◽

10.1016/j.commatsci.2013.09.058 ◽

2014 ◽

Vol 82 ◽

pp. 197-201 ◽

Cited By ~ 22

Author(s):

Ali Ahmadi Peyghan ◽

Maziar Noei

Keyword(s):

Hydrogen Fluoride ◽

Computational Study ◽

Si Doped ◽

Bc2n Nanotubes

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CO oxidation over the polyoxometalate-supported single-atom catalysts M1/POM (Fe, Co, Mn, Ru, Rh, Os, Ir, and Pt; POM = [PW12O40]3–): a computational study on the activation of surface oxygen species

Dalton Transactions ◽

10.1039/c8dt03843k ◽

2019 ◽

Vol 48 (18) ◽

pp. 6228-6235 ◽

Cited By ~ 3

Author(s):

Chun-Guang Liu ◽

Li-Long Zhang ◽

Xue-Mei Chen

Keyword(s):

Density Functional Theory ◽

Co Oxidation ◽

Density Functional ◽

Computational Study ◽

Density Functional Theory Calculations ◽

Catalytic Performance ◽

Single Atom ◽

Oxygen Species ◽

Surface Oxygen ◽

Functional Theory

Density functional theory calculations have been carried out to explore the catalytic performance of a series of the M1/POM (M = Fe, Co, Mn, Ru, Rh, Os, Ir, and Pt; POM = [PW12O40]3−) single-atom catalysts for CO oxidation.

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