Intrinsic acid resistance and high removal performance from the incorporation of nickel nanoparticles into nitrogen doped tubular carbons for environmental remediation

Nitrogen doped tubular magnetic carbons embedded with nickel nanoparticles (Ni@NTMCs) were prepared via a simple pyrolysis process and employed as the effective adsorbents for the Cr(VI) removal. Ni@NTMCs with as high as 10.63 at.% N doping exhibited the excellent Cr(VI) removal capacities of 24.4 and 250 mg g(-1) in neutral and acidic solution, respectively. Adsorption kinetics and isotherm study revealed that the monolayer chemical adsorption was the rate-controlling step for the Cr(VI) removal. The high removal performance can be ascribed to the combination of adsorption and reduction reaction between Cr(VI) ions, and Ni nanoparticles. N dopant and edge carbons acted as the Cr(VI) adsorption site. The surface Ni nanoparticles mainly made contributions to the reduction process. The embedded Ni nanoparticles steadily provided magnetism for the separation and helpful for the recycles stability, showing a high acid corrosion resistance in this study. (C) 2020 Elsevier Inc. All rights reserved.