Preparation of Nitrogen-Doped Carbon Materials from Monosodium Glutamate and Application in Reduction of p-Nitrophenol

Abstract

Nitrogen-doped carbons (NCs) as supports for metal catalysts used in heterogeneous reactions are increasingly being investigated. In this work, NCs were prepared from monosodium glutamate (MSG) by direct carbonization, which were used as supporters to prepare Bi/NC catalysts. The Bi/NC catalysts were characterized by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and nitrogen adsorption isotherm. The results indicate that nitrogen was doped in the formation of pyridinic N, pyrrolic N, and graphitic N. The NCs possess high surface area (~652 m 2 /g) and uniform mesopore size (~2.11 nm). Bismuth nanoparticles (NPs) dispersed uniformly in NC with diameter of 10-20 nm. The catalytic performances were investigated using the reduction of 4-nitrophenol (4-NP) with excess potassium borohydride as a model reaction, the results indicating that the Bi/NC catalysts have higher activity and better reusability than the Bi/AC catalyst. Under the following conditions: 100 mL of 4-NP (2 mM), 0.03 g of 3%Bi/NC, n(KBH4) : n(4-NP) = 40:1, and at room temperature, the rate constant k can reach 0.31 min -1 .

Preparation of Nitrogen-Doped Carbon Material from Monosodium Glutamate and Its Catalytic Performance

“…Therefore, the reaction can be regarded as pseudo-first-order reaction. Since the absorbance of 4-NP is proportional to its concentration in the mixture, the ratio of At/A0 is equal to the concentration ratio Ct/C0 of 4-NP [18]. Hence, the kinetic equation for the reduction can be written as Equation (3).…”

“…Therefore, the catalytic reduction of 4-NP to 4-AP with NaBH4 has been widely studied. Most of the existing researches on the reaction are based on metallic catalysts, such as: Ag [14], Au [15], Cu [16], Co [17], and Bi [18], which are restricted due to limited reserves, high cost and low stability.…”