Cobalt-based nanocatalysts for green oxidation and hydrogenation processes

Jagadeesh, Rajenahally V.; Stemmler, Tobias; Surkus, Annette‐Enrica; Bauer, Matthias; Pohl, Marga‐Martina; Radnik, Jörg; Junge, Kathrin; Junge, Henrik; Brückner, Angelika; Beller, Matthias

doi:10.1038/nprot.2015.049

Cited by 120 publications

(68 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Beller et al. suggested that metal oxide nanoparticles catalyze the oxidation of the −OH group to the corresponding −CHO with K 2 CO 3 as the additive for expediting the hydrogen abstraction . Conversely, CoO x ‐N/C here achieved excellent performance in neutral medium.…”

Section: Methodsmentioning

confidence: 95%

A High‐Performance Base‐Metal Approach for the Oxidative Esterification of 5‐Hydroxymethylfurfural

Sun

Jia

et al. 2016

ChemCatChem

View full text Add to dashboard Cite

Exploring high‐performance base‐metal approaches for the sustainable production of chemicals from biomass is presently attracting immense interest and is truly important to promote their industrialized application. Herein, CoOx‐N/C and α‐MnO2 were combined as a base‐metal catalyst that can achieve high yields of furan‐2,5‐dimethylcarboxylate (FDMC, 95.6 %) for the catalytic oxidative esterification of 5‐hydroxymethylfurfural (HMF) without basic additive. The reaction proceeds through fast conversion of HMF to diformylfuran (DFF) with α‐MnO2 and subsequent transformation of DFF to FDMC by CoOx‐N/C. Quantitative X‐ray photoelectron spectroscopy (XPS) analysis and density functional theory (DFT) calculations indicated that the pyridinic‐N present in doped carbon could behave as a Lewis base to promote the abstraction of hydrogen for the oxidative esterification reaction. Consequently, CoOx‐N/C is a high performance catalyst for the synthesis of FDMC from DFF in a neutral medium.

show abstract

Section: Methodsmentioning

confidence: 95%

A High‐Performance Base‐Metal Approach for the Oxidative Esterification of 5‐Hydroxymethylfurfural

Sun

Jia

et al. 2016

ChemCatChem

View full text Add to dashboard Cite

show abstract

“…Recently, non‐noble‐metal nanoparticles supported on nitrogen‐doped carbon have attracted attention as substitutes for noble‐metal catalysts in various redox reactions . Particularly, Beller and coworkers have developed heterogeneous cobalt catalysts by simple pyrolysis of Co complexes with nitrogen‐containing ligands on carbon supports . These catalysts have shown high activity and selectivity for several applications such as hydrogenation of nitroarenes, oxidative esterification, and recently dehydrogenation of formic acid .…”

Section: Figurementioning

confidence: 99%

Lignin Valorization by Cobalt‐Catalyzed Fractionation of Lignocellulose to Yield Monophenolic Compounds

et al. 2018

View full text Add to dashboard Cite

Herein, a catalytic reductive fractionation of lignocellulose is presented using a heterogeneous cobalt catalyst and formic acid or formate as a hydrogen donor. The catalytic reductive fractionation of untreated birch wood yields monophenolic compounds in up to 34 wt % yield of total lignin, which corresponds to 76 % of the theoretical maximum yield. Model compound studies revealed that the main role of the cobalt catalyst is to stabilize the reactive intermediates formed during the organosolv pulping by transfer hydrogenation and hydrogenolysis reactions. Additionally, the cobalt catalyst is responsible for depolymerization reactions of lignin fragments through transfer hydrogenolysis reactions, which target the β‐O‐4′ bond. The catalyst could be recycled three times with only negligible decrease in efficiency, showing the robustness of the system.

show abstract

“…The procedure was adapted from that reported for the synthesis of Co/Phen based catalysts [58]. Cobalt(II) acetate tetrahydrate was added to absolute ethanol (40 mL of EtOH for 1 mmol of Co(OAc)2·4H2O) and stirred until complete solubilization (10 min., formation of a clear purple solution).…”

Section: Catalysts Preparationmentioning

confidence: 99%

“…Hence, merging rationally-designed suitable modified supports with cheap transition metals permits access to the design of active, selective and cheap catalytic materials thus allowing to match or to outperform noble-metal-based catalysts. During the last three years, some of us reported the preparation of active and selective NGr-decorated Co-based catalysts from the pyrolysis of in situ generated 1,10-phenanthroline (Phen) metal complexes using Vulcan® XC 72 R carbon [52][53][54][55][56][57][58][59][60], ceria [61] or α-alumina as supports [62]. Some of the obtained nanoscale catalysts exhibit a core-shell architecture in which a Co metallic core is enveloped by an oxidic sheath composed of Co3O4.…”

Section: Introductionmentioning

confidence: 99%

Co-based heterogeneous catalysts from well-defined α-diimine complexes: Discussing the role of nitrogen

Formenti

Ferretti

Topf

et al. 2017

Journal of Catalysis

Self Cite

View full text Add to dashboard Cite

‡ These authors contributed equally to this work.Abstract: Ar-BIANs and related α-diimine Co complexes were wet impregnated onto Vulcan® XC 72 R carbon black powder and used as precursors for the synthesis of heterogeneous supported nanoscale catalysts by pyrolysis under argon at 800 °C. The catalytic materials feature a core-shell structure composed of metallic Co and Co oxides decorated with nitrogen-doped graphitic layers (NGr). These catalysts display high activity in the liquid phase hydrogenation of aromatic nitro compounds (110 °C, 50 bar H2) to give chemoselectively substituted aryl amines. The catalytic activity is closely related to the amount and type of nitrogen atoms in the final catalytic material, which suggests a heterolytic activation of dihydrogen.Keywords: cobalt, hydrogenation, nitro compounds, kinetic, heterolytic activation IntroductionCatalysis is a key-technology for the manufacturing of all kinds of bulk and fine chemical products. It allows for producing chemicals avoiding the formation of undesired and useless stoichiometric side products which leads to additional cost and energy consumption [1][2][3]. Many of the industrially relevant catalytic processes in the fine chemical industry are still based on expensive and rare late transition metals such as Pd, Pt, Rh, Ru and Ir [4,[1][2][3][4][5]. Although these metals exhibit very good catalytic performance for advanced organic substrates, the decreasing availability of these elements requires the development of efficient alternative metal-based catalysts [6]. In this regard, the design of catalytic systems based on abundant and biocompatible metals is an important goal for the implementation and progress of green and sustainable chemistry. Hence, transition metals such as Fe, Co and Cu are ideal candidates, which meet these requirements [7][8][9][10]. As a matter of fact, these elements are among the most abundant metals in the Earth's upper crust, thus being readily accessible [11]. Recently, heteroatom-doped carbon materials attracted major interest in the field of metal supported heterogeneous catalysts for both chemical synthesis [12][13][14] and/or energy-relevant transformations [15,16]. Indeed, doping graphene with heteroatoms such as N, B, P, or S leads to a radical modification of the electronic properties of both the support and the supported metal [17][18][19]. Consequently, it is possible to modify the activity and adjust the selectivity of the final catalytic material towards the desired transformation. Among the various dopants, nitrogen attracted most interest [15,[20][21][22]. and applications of transition metal/N-doped graphene (NGr) based catalytic systems ranges from oxygen reduction reactions (ORR) [23][24][25][26], hydrogen evolving reactions (HER) [27,28], photocatalysis [29,30], oxidation [31][32][33][34][35][36][37][38], and reduction [39][40][41][42][43][44] reactions of organic

show abstract

Cobalt-based nanocatalysts for green oxidation and hydrogenation processes

Cited by 120 publications

References 22 publications

A High‐Performance Base‐Metal Approach for the Oxidative Esterification of 5‐Hydroxymethylfurfural

A High‐Performance Base‐Metal Approach for the Oxidative Esterification of 5‐Hydroxymethylfurfural

Lignin Valorization by Cobalt‐Catalyzed Fractionation of Lignocellulose to Yield Monophenolic Compounds

Co-based heterogeneous catalysts from well-defined α-diimine complexes: Discussing the role of nitrogen

Contact Info

Product

Resources

About