Co–N–C-Supported Platinum Catalyst: Synergistic Effect on the Aerobic Oxidation of Glycerol

Abstract

Metal-and nitrogen-doped carbon materials (Me− N−C) have received intensive scientific interest as single-atom catalysts (SACs) for electro-and thermocatalytic reactions. In this work, the potential of Me−N−C (Me = Co, Fe, Ni)-wrapped carbon nanotubes (CNTs) as support of platinum nanoparticles (Pt NPs) for base-free oxidation of glycerol was investigated. Codoping of transition metal and nitrogen significantly enhanced the dispersion of Pt, indicating the advantages of the supporting material for noble-metal catalysts. Two-fold improvement of turnover of glycerol was observed over 5Pt/CoNC@CNT compared to 5Pt/CNT under the same reaction conditions. A kinetics study was conducted to understand the role of CoNC as a support of Pt NPs in a wide range of oxygen partial pressure from 0.04 to 0.4 MPa and a range of glycerol concentration from 0.012 to 0.15 wt %. A synergistic effect between Me−N−C, especially Co−N− C, and Pt NPs was revealed. The Co−N−C support facilitated the activation of oxygen and thus enhanced the overall turnover of glycerol oxidation, especially at high glycerol concentrations. This finding suggests a new approach to the high-performance Pt catalysts via introducing SACs as supporting materials that afford auxiliary active sites for the target reaction.

Tuning the Product Selectivity toward the High Yield of Glyceric Acid in Pt−CeO2/CNT Electrocatalyzed Oxidation of Glycerol

“…The rational design of the electrocatalysts is the key to the green and high efficient electrocatalytic glycerol oxidation process. Recently, various noble metal‐based catalysts with well‐defined compositions, sizes, morphologies, and structures have been prepared for the improved electrocatalytic activity [22–25] . Despite enormous achievements, it remains a big challenge to simultaneously realize the multiple performances of the electrocatalyst with high activity, desirable GLYA selectivity, together with low noble metal usage [26–29] .…”

“…Recently, various noble metal-based catalysts with well-defined compositions, sizes, morphologies, and structures have been prepared for the improved electrocatalytic activity. [22][23][24][25] Despite enormous achievements, it remains a big challenge to simultaneously realize the multiple performances of the electrocatalyst with high activity, desirable GLYA selectivity, together with low noble metal usage. [26][27][28][29] Compared with the acid medium, Pt, or Au-based catalysts typically exhibit higher catalytic activity in alkaline solutions.…”

Hollow Carbon Cages Derived from Polyoxometalate‐Encapsuled Metal‐Organic Frameworks for Energy‐Saving Hydrogen Production

“…To date, two strategies have emerged, one of which is to develop advanced OER electrocatalyst, [19–21] and the other is to replace OER with other anodic oxidation reactions with faster kinetics, such as alcohol, [22,23] urea [24,25] and hydrazine [26–28] oxidation reactions. Among these reactions, the glycerol/glucose oxidation reaction provides a promising way for production of high‐purity hydrogen and value‐added chemicals [29–31] …”

Cobalt/Cobalt Oxide Nanorods-Decorated Reduced Graphene Oxide (Co/Co3O4-rGO) for Enhanced Electrooxidation of Glycerol

“…Various studies on water and glycerol electrooxidation processes have been reported for noble-metal-free materials, mostly in alkaline conditions, and they are receiving global interest due to their low cost, natural abundance, excellent conductivity, and remarkable stability, – with the majority of them using a combination of other metal oxides or heteroatom-doped carbon-based systems. – More specifically, cobalt is naturally abundant, less toxic, cost-effective, and electrochemically highly stable, and cobalt decorated on graphene systems shows superior electrochemical OER and GOR . Because of its extraordinarily high surface area, excellent conductivity, and easy and recognized synthesis techniques, Co 3 O 4 is one of the numerous transition-metal oxides that is appealing for energy storage devices .…”