N-Doped Mesoporous Carbons: From Synthesis to Applications as Metal-Free Reduction Catalysts and Energy Storage Materials

Abstract

N-doped mesoporous carbons, NMCs, have attracted intensive attention recently and have shown potential applications in various scientific fields including catalysis and energy conversion/storage. Via modification with foreign N elements and construction of mesoporous structures for NMCs, their electronic and spin structure, as well as their porosity can be greatly tailored. And the resultant electron-donor property, surface wettability, conductivity, ion/molecular transfer and reactivity are changed accordingly. In this review, we will summarize the recent research progress of these metal-free NMCs, with an emphasis on their synthesis and performance, especially for their synthetic strategy and catalytic properties toward oxygen and nitro compound reductions, as well as their electrochemical properties as electrode materials for lithium-ion/sulfur batteries and supercapacitors. We hope for future developments, such as controlling doping methods more precisely, generating more active sites by N-doping, and finding wider applications of NMCs in other fields.

Recent advances in metal-free heteroatom-doped carbon heterogonous catalysts

“…167 Normally, the presence of nitrogen atoms in the carbon skeleton affords basic property, which boosts the interaction between carbon surface and acidic molecules. [168][169][170][171][172] More importantly, N doping can greatly inuence the charge distribution and spin density of carbon atoms because of the different electronegativity of carbon (2.55) and nitrogen (3.04), leading to the formation of defects in the carbon framework. This in turn can alter the electronic structure of carbon compounds.…”

Mesoporous Carbon of Carbonized Human Urine Waste: A Valuable Heterogeneous Catalyst for Chromene and Xanthene Derivative Synthesis

“…The surface chemical compositions and oxidation states of elements were determined using the XPS survey spectrum, as shown in Figure S1, supporting the presence of the C, Na, Cl, P, and N as major elements of HUC, and K, S, and Si as minor elements (Table S1). It was experimentally accepted that a heteroatom can introduce defects into the carbon backbone that facilitates ion transport rate, which significantly increases the catalyst reaction rate/activity [31]. The incorporation of heteroatoms into porous carbon may increase electrical conductivity, influence surface wettability, inducing a negative charge on the carbon surface and enhancing the electro-active surface area [32].…”

Synthesis of Multiporous Carbons from the Water Caltrop Shell for High-Performance Supercapacitors

“…Because of their low pore volume, the commercially available microporous carbons (pore size < 2 nm) are not very attractive. 5 Therefore, it is a key issue to design a nanostructured porous carbon with pore properties specifically tailored for the supercapacitor application. 6 Nowadays, porous carbon materials are widely utilized as electrode materials for supercapacitors owing to their low cost, excellent cycle stability, and easy manufacturing.…”

“…However, the limitation of its low energy density increases both the volume and cost of the device. Because of their low pore volume, the commercially available microporous carbons (pore size < 2 nm) are not very attractive . Therefore, it is a key issue to design a nanostructured porous carbon with pore properties specifically tailored for the supercapacitor application …”