Metal-Free Carbon Nanomaterials Become More Active than Metal Catalysts and Last Longer

Abstract

Many reactions involve metals, especially noble metals or metal oxides as catalysts. Although metal-based catalysts have been playing a major role in various industrial processes, they still suffer from multiple competitive disadvantages, including their high cost, susceptibility to gas poisoning, and detrimental effects on the environment. Owing to their wide availability, environmental acceptability, corrosion resistance, and unique surface properties, certain carbon nanomaterials have recently been demonstrated to be promising metal-free alternatives for low-cost catalytic processes. This perspective highlights recent progresses in the development of carbon-based metal-free catalysts. Scheme 1. ODH of (1) Ethylbenzene and (2) Alkanes (a) and ORR in Alkaline (b) and Acidic (c) Media

Tuning CNT Properties for Metal-Free Environmental Catalytic Applications

“…The exceptional electronic properties and catalytic performances of N-doped carbon nanotubes are attracting much interest [11,25,40,41]. The incorporation of nitrogen atoms onto the carbon structure is relatively easy due to the similar sizes of the nitrogen and carbon atoms [42,43], providing additional electrons for the graphitic lattice [44].…”

Catalytic performance of carbon nanotubes in H2O2 decomposition: Experimental and quantum chemical study

“…Besides serving as a support, CNTs alone can be used as catalysts for some specific reactions, including methane and NO x decomposition [3,4], oxidative dehydrogenization of aromatic hydrocarbons and alkanes [5,6,7,8,9], oxidation of aniline [10], p-toluidine [11], and benzyl alcohol [12], catalytic wet air oxidation of phenol [13,14] and pcoumaric acid [15,16], aerobic oxidation of cyclohexane [17,18], ozonation of oxalic acid [19,20], selective oxidation of H 2 S [21], and heterogeneous hydroxylation of organics [22]. Nitrogen-doped CNTs were used as basic catalyst in Knoevenagel condensation [23] and CO oxidation [24] reactions.…”

Carbon-Based Metal-Free Electrocatalysis for Energy Conversion, Energy Storage, and Environmental Protection

“…High surface area is another important property of CNTs, with theoretical surface areas of SWCNTs reaching 1315 m 2 g −1 [48]. Because of the unique structures and extraordinary electrical, mechanical, and optical properties, CNTs are promising for various applications [49][50][51], ranging from composite materials to electronic and energy-related devices [52][53][54][55][56][57][58].…”