Microporous N-Doped Carbon Obtained from Salt Melt Pyrolysis of Chitosan toward Supercapacitor and Oxygen Reduction Catalysts

Abstract

The direct carbonization of low-cost and abundant chitosan biopolymer in the presence of salt eutectics leads to highly microporous, N-doped nanostructures. The microporous structure is easily manufactured using eutectic mixture (ZnCl2-KCl) and chitosan. Potassium ions here can act as an intercalating agent, leading to the formation of lamellar carbon sheets, whereas zinc chloride generates significant porosity. Here, we present an efficient synthetic way for microporous carbon nanostructures production with a total nitrogen content of 8.7%. Preliminary studies were performed to show the possibility of the use of such material as a catalyst for supercapacitor and ORR. The textural properties enhanced capacitance, which stem from improved accessibility of previously blocked or inactive pores in the carbon structure, leading to the conclusion that porogen salts and molten salt strategies produce materials with tailor-made morphologies. The synergistic effect of the eutectic salt is seen in controlled porous structures and pore size, and the micropores boosting adsorption ability.

Binder-free MoSe/MMSe composite and onion-derived activated carbon electrode materials for high-performance hybrid supercapacitors

“…4(h), the core-level HR XPS spectrum of the C 1s contained six peaks at 283.8, 284.1, 285.1, 286.1, 287.1, and 288.1 eV, which are related to carbide carbon, CC, C–C, C–O, CO, and O–CO bonds, respectively. 47,48 In the HR XPS spectrum of N 1s (Fig. 4(i)), a peak at 400.1 eV was observed, indicating the presence of NC bonds.…”

Chitosan-Derived Nitrogen-Doped Carbon as a Support of Cobalt(II)-Phthalocyanine/Gold Nanoparticles for Photocatalytic Water Splitting

“…This biopolymer could be the fascinating precursor for the synthesis of nitrogen-doped carbon (NC) by a thermal decomposition reaction because it could provide both nitrogen and carbon atoms for the construction. − This facile, effective, and inexpensive pathway provides NC for various purposes, in particular, it generates an optically active support for the photocatalysts . The obtained NC has some characteristics such as strongly anchoring to the transition metals, high optical activity, generating n-type semiconductor, and sustainability. − This kind of semiconductor easily retards charge recombination due to the presence of nitrogen atoms, which leads to the durability of the photocatalyst . Moreover, abundance of nitrogen atoms in the chitosan structure leads to the high content of this atom in the synthesized NC, which in turn affords remarkable active sites to the deposition of transition metals. , NC is considered a promising support for the photocatalytic hydrogen generation since protons easily are promoted to H 2 after binding to the nitrogen .…”

“… 8 The obtained NC has some characteristics such as strongly anchoring to the transition metals, high optical activity, generating n-type semiconductor, and sustainability. 9 − 13 This kind of semiconductor easily retards charge recombination due to the presence of nitrogen atoms, which leads to the durability of the photocatalyst. 14 Moreover, abundance of nitrogen atoms in the chitosan structure leads to the high content of this atom in the synthesized NC, which in turn affords remarkable active sites to the deposition of transition metals.…”

Self-Templating Synthesis of N/P/Fe Co-Doped 3D Porous Carbon for Oxygen Reduction Reaction Electrocatalysts in Alkaline Media

“…Generally, the catalytic performance of carbon-based doped catalysts depends on the specific surface area and pore structure, the composition, content, and distribution of doped elements [18][19][20][21]. Conventional synthetic techniques are mainly obtained by porous templates at high carbonization temperatures [22,23]. However, template-assisted methods often require additional complex processes to synthesize and remove templates (for example, silica, polystyrene spheres or metal oxides), during which toxic reagents may be introduced, causing the catalyst to be poisoned.…”