Influence of alkali metals on Pd/TiO2 catalysts for catalytic oxidation of formaldehyde at room temperature

The reduction of the relatively inert carbon–oxygen bonds of CO2 to access useful CO2-derived organic products is one of the most important fundamental challenges in synthetic chemistry. Facilitating this bond-cleavage using earth-abundant, non-toxic main group elements (MGEs) is especially arduous because of the difficulty in achieving strong inner-sphere interactions between CO2 and the MGE. Herein we report the first successful chemical reduction of CO2 at room temperature by alkali metals, promoted by a cyclic(alkyl)(amino) carbene (CAAC). One-electron reduction of CAAC-CO2 adduct (1) with lithium, sodium or potassium metal yields stable monoanionic radicals clusters [M(CAAC–CO2)]n(M = Li, Na, K, 2-4) and two-electron alkali metal reduction affords open-shell, dianionic clusters of the general formula [M2(CAAC–CO2)]n (5-8). It is notable that these crystalline clusters of reduced CO2 may also be isolated via the “one-pot” reaction of free CO2 with free CAAC followed by the addition of alkali metals – a reductive process which does not occur in the absence of carbene. Each of the products 2-8 were investigated using a combination of experimental and theoretical methods.

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Double graphitic-N doping for enhanced catalytic oxidation activity of carbocatalysts

Physical Chemistry Chemical Physics ◽

10.1039/c8cp07317a ◽

2019 ◽

Vol 21 (10) ◽

pp. 5481-5488 ◽

Cited By ~ 5

Author(s):

Meiling Hou ◽

Xin Zhang ◽

Shandong Yuan ◽

Wanglai Cen

Keyword(s):

Work Function ◽

Catalytic Oxidation ◽

Functional Groups ◽

Reactive Oxygen ◽

Catalytic Efficiency ◽

Oxidation Activity ◽

Promotion Effect ◽

Oxygen Functional Groups ◽

N Doping

Double-GrN remarkably enhanced the catalytic efficiency for O2 dissociation reactions and accelerates the generation of highly chemically reactive oxygen functional groups. The promotion effect is ascribed to the reduction of the work function of carbocatalysts due to N doping, which facilitates the transfer of electrons from carbocatalysts to the adsorbed O2 molecules for their activation.

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A single iron site confined in a graphene matrix for the catalytic oxidation of benzene at room temperature

Science Advances ◽

10.1126/sciadv.1500462 ◽

2015 ◽

Vol 1 (11) ◽

pp. e1500462 ◽

Cited By ~ 376

Author(s):

Dehui Deng ◽

Xiaoqi Chen ◽

Liang Yu ◽

Xing Wu ◽

Qingfei Liu ◽

...

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Low Temperature ◽

Catalytic Oxidation ◽

Room Temperature ◽

Single Atom ◽

Intermediate Structure ◽

Oxidation Reactions ◽

Transmission Electron ◽

Oxidation Of Benzene

Coordinatively unsaturated (CUS) iron sites are highly active in catalytic oxidation reactions; however, maintaining the CUS structure of iron during heterogeneous catalytic reactions is a great challenge. Here, we report a strategy to stabilize single-atom CUS iron sites by embedding highly dispersed FeN4 centers in the graphene matrix. The atomic structure of FeN4 centers in graphene was revealed for the first time by combining high-resolution transmission electron microscopy/high-angle annular dark-field scanning transmission electron microscopy with low-temperature scanning tunneling microscopy. These confined single-atom iron sites exhibit high performance in the direct catalytic oxidation of benzene to phenol at room temperature, with a conversion of 23.4% and a yield of 18.7%, and can even proceed efficiently at 0°C with a phenol yield of 8.3% after 24 hours. Both experimental measurements and density functional theory calculations indicate that the formation of the Fe═O intermediate structure is a key step to promoting the conversion of benzene to phenol. These findings could pave the way toward highly efficient nonprecious catalysts for low-temperature oxidation reactions in heterogeneous catalysis and electrocatalysis.

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Dual-dehydrogenation-promoted catalytic oxidation of formaldehyde on alkali-treated Pt clusters at room temperature

Journal of Materials Chemistry A ◽

10.1039/c5ta00778j ◽

2015 ◽

Vol 3 (19) ◽

pp. 10432-10438 ◽

Cited By ~ 29

Author(s):

Peng Zhou ◽

Jiaguo Yu ◽

Longhui Nie ◽

Mietek Jaroniec

Keyword(s):

Catalytic Oxidation ◽

Room Temperature ◽

Pt Catalysts

Dual dehydrogenation of HCHO molecules can promote the activation of O2 molecules and regeneration of Pt catalysts.

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ChemInform Abstract: Birch Reductions at Room Temperature with Alkali Metals in Silica Gel (Na2K-SG(I)).

ChemInform ◽

10.1002/chin.200952038 ◽

2009 ◽

Vol 40 (52) ◽

Author(s):

Partha Nandi ◽

James L. Dye ◽

James E. Jackson

Keyword(s):

Silica Gel ◽

Alkali Metals ◽

Room Temperature

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SiO2‐Si interface formation by catalytic oxidation using alkali metals and removal of the catalyst species

Journal of Applied Physics ◽

10.1063/1.337485 ◽

1986 ◽

Vol 60 (12) ◽

pp. 4339-4341 ◽

Cited By ~ 83

Author(s):

P. Soukiassian ◽

T. M. Gentle ◽

M. H. Bakshi ◽

Z. Hurych

Keyword(s):

Catalytic Oxidation ◽

Alkali Metals ◽

Interface Formation

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Surface oxygen vacancies on Co3O4 mediated catalytic formaldehyde oxidation at room temperature

Catalysis Science & Technology ◽

10.1039/c5cy01709b ◽

2016 ◽

Vol 6 (11) ◽

pp. 3845-3853 ◽

Cited By ~ 103

Author(s):

Zhong Wang ◽

Wenzhong Wang ◽

Ling Zhang ◽

Dong Jiang

Keyword(s):

Catalytic Oxidation ◽

Room Temperature ◽

Oxygen Vacancies ◽

Essential Role ◽

Surface Oxygen ◽

Oxidation Reactions ◽

Major Activity ◽

Formaldehyde Oxidation ◽

The Common

This study reveals the essential role played by surface oxygen vacancies in catalytic oxidation reactions, and complements the common viewpoint that Co3+ is the major activity species in Co3O4-based systems.

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