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

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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Role of Chemical Structure of Support in Enhancing the Catalytic Activity of a Single Atom Catalyst Toward NRR: A Computational Study

Frontiers in Chemistry ◽

10.3389/fchem.2021.733422 ◽

2021 ◽

Vol 9 ◽

Author(s):

Thillai Govindaraja Senthamaraikannan ◽

Selvaraj Kaliaperumal ◽

Sailaja Krishnamurty

Keyword(s):

Metal Atom ◽

Density Functional ◽

Computational Study ◽

Molecular Nitrogen ◽

Red Shift ◽

Single Atom ◽

Metal Atoms ◽

Doped Graphene ◽

Adsorption Energies

Using the periodic density functional theory–based methodology, we propose a potential catalytic system for dinitrogen activation, viz., single metal atoms (Mo, Fe, and V) supported on graphene-based sheets. Graphene-based sheets show an excellent potential toward the anchoring of single atoms on them (Mo, Fe, and V) with adsorption energies ranging between 1.048 and 10.893 eV. Factors such as defects and BN doping are noted to enhance the adsorption energies of single metal atoms on the support. The adsorption of a dinitrogen molecule on metal atom–anchored graphene-based supports is seen to be highly favorable, ranging between 0.620 and 2.278 eV. The adsorption is driven through a direct hybridization between the d orbitals of the metal atom (Mo, Fe, and V) on the support and the p orbital of the molecular nitrogen. Noticeably, BN-doped graphene supporting a single metal atom (Mo, Fe, and V) activates the N2 molecule with a red shift in the N–N stretching frequency (1,597 cm−1 as compared to 2,330 cm−1 in the free N2 molecule). This red shift is corroborated by an increase in the N–N bond length (1.23 Å from 1.09 Å) and charge transfer to an N2 molecule from the catalyst.

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CO2electroreduction performance of a single transition metal atom supported on porphyrin-like graphene: a computational study

Physical Chemistry Chemical Physics ◽

10.1039/c7cp04299j ◽

2017 ◽

Vol 19 (34) ◽

pp. 23113-23121 ◽

Cited By ~ 52

Author(s):

Zhongxu Wang ◽

Jingxiang Zhao ◽

Qinghai Cai

Keyword(s):

Catalytic Activity ◽

Transition Metal ◽

Metal Atom ◽

Computational Study ◽

Transition Metal Atom ◽

High Catalytic Activity ◽

Metal Atoms ◽

Transition Metal Atoms ◽

Single Transition

Single transition metal atoms supported by porpyrin-like graphene exhibit high catalytic activity for the electroreduction of CO2.

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Linking Bi-Metal Distribution Patterns in Porous Carbon Nitride Fullerene to Its Catalytic Activity toward Gas Adsorption

Nanomaterials ◽

10.3390/nano11071794 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1794

Author(s):

Parisa Nematollahi ◽

Erik C. Neyts

Keyword(s):

Catalytic Activity ◽

Carbon Nitride ◽

Gas Adsorption ◽

Distribution Patterns ◽

Catalyst Design ◽

Metal Distribution ◽

Binary Complex ◽

Metal Atoms ◽

Metal Composition ◽

Single Transition

Immobilization of two single transition metal (TM) atoms on a substrate host opens numerous possibilities for catalyst design. If the substrate contains more than one vacancy site, the combination of TMs along with their distribution patterns becomes a design parameter potentially complementary to the substrate itself and the bi-metal composition. By means of DFT calculations, we modeled three dissimilar bi-metal atoms (Ti, Mn, and Cu) doped into the six porphyrin-like cavities of porous C24N24 fullerene, considering different bi-metal distribution patterns for each binary complex, viz. TixCuz@C24N24, TixMny@C24N24, and MnyCuz@C24N24 (with x, y, z = 0–6). We elucidate whether controlling the distribution of bi-metal atoms into the C24N24 cavities can alter their catalytic activity toward CO2, NO2, H2, and N2 gas capture. Interestingly, Ti2Mn4@C24N24 and Ti2Cu4@C24N24 complexes showed the highest activity and selectively toward gas capture. Our findings provide useful information for further design of novel few-atom carbon-nitride-based catalysts.

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Catalytic activity of palladium-doped silver dilute nanoalloys for formate oxidation from a theoretical perspective

Physical Chemistry Chemical Physics ◽

10.1039/c9cp04530a ◽

2019 ◽

Vol 21 (40) ◽

pp. 22598-22610 ◽

Cited By ~ 20

Author(s):

Nan Zhang ◽

Fuyi Chen ◽

Longfei Guo

Keyword(s):

Catalytic Activity ◽

Oxidation Reaction ◽

Theoretical Perspective ◽

Single Atom ◽

High Catalytic Activity ◽

Formate Oxidation ◽

First Time ◽

Single Atom Alloys

We demonstrate for the first time that the Pd1Ag single-atom alloys exhibit a high catalytic activity for formate oxidation reaction.

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Ultrahigh surface density of Co-N2C single-atom-sites for boosting photocatalytic CO2 reduction to methanol

Applied Catalysis B Environmental ◽

10.1016/j.apcatb.2021.120695 ◽

2022 ◽

Vol 300 ◽

pp. 120695 ◽

Cited By ~ 1

Author(s):

Minzhi Ma ◽

Zeai Huang ◽

Dmitry E. Doronkin ◽

Wenjun Fa ◽

Zhiqiang Rao ◽

...

Keyword(s):

Surface Density ◽

Co2 Reduction ◽

Single Atom

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First-principles screening of single transition metal atoms anchored on two-dimensional C9N4 for the nitrogen reduction reaction

Physical Chemistry Chemical Physics ◽

10.1039/d0cp06617f ◽

2021 ◽

Vol 23 (14) ◽

pp. 8784-8791

Author(s):

Qingling Meng ◽

Ling Zhang ◽

Jinge Wu ◽

Shuwei Zhai ◽

Xiamin Hao ◽

...

Keyword(s):

Nitrogen Fixation ◽

Transition Metal ◽

First Principles ◽

Reduction Reaction ◽

Single Atom ◽

Two Dimensional ◽

Metal Atoms ◽

Transition Metal Atoms ◽

Catalytically Active ◽

Single Transition

Theoretical screening of transition metal atoms anchored on monolayer C9N4 as highly stable, catalytically active and selective single-atom catalysts for nitrogen fixation.

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Engineering Mn Atomic Sites in Multi-Dimensional Nitrogen-Doped Carbon for Highly Efficient Oxygen Reduction Reaction

Chemical Communications ◽

10.1039/d1cc06811c ◽

2022 ◽

Author(s):

Huixin Ma ◽

Daijie Deng ◽

Honghui Zhang ◽

Feng Chen ◽

Junchao Qian ◽

...

Keyword(s):

Catalytic Activity ◽

Oxygen Reduction Reaction ◽

Oxygen Reduction ◽

Reduction Reaction ◽

Single Atom ◽

Two Dimensional ◽

One Dimensional ◽

Nitrogen Doped ◽

Half Wave ◽

Nitrogen Doped Carbon

Nitrogen-coordinated single-atom manganese in multi-dimensional nitrogen-doped carbon electrocatalysts (Mn-NC) was successful constructed by combing two-dimensional nanosheets and one-dimensional nanofibers. The Mn-NC exhibited excellent oxygen reduction reaction catalytic activity with half-wave...

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73Ge, 119Sn and 207Pb: general cooperative effects of single atom ligands on the NMR signals observed in tetrahedral [MXnY4−n] (M = Ge, Sn, Pb; 1 ≤ n ≤ 4; X, Y = Cl, Br, I) coordination compounds of heavier XIV group elements

Dalton Transactions ◽

10.1039/c7dt00307b ◽

2017 ◽

Vol 46 (9) ◽

pp. 2855-2860 ◽

Cited By ~ 4

Author(s):

M. Benedetti ◽

F. De Castro ◽

F. P. Fanizzi

Keyword(s):

Linear Relationship ◽

Coordination Compounds ◽

Chemical Shifts ◽

Single Atom ◽

Ionic Radii ◽

Nmr Chemical Shifts ◽

Cooperative Effects ◽

Nmr Signals

An inverse linear relationship between 73Ge, 119Sn and 207Pb NMR chemical shifts and the sum of ionic radii of coordinated halides has been found in [MXnYm] (M = Ge, Sn, Pb; n + m = 4; X, Y = Cl, Br, I) compounds.

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