Simple coordination complex-derived Ni NP anchored N-doped porous carbons with high performance for reduction of nitroarenes

Abstract

Coordination complexes are ideal sacrificial templates for fabricating their respective derivatives by changing the thermal conditions. In this study, nitrogen-doped hierarchical porous carbons anchored with nickel nanoparticles (Ni NPs) were prepared by using rod-like nickel dimethylglyoximate [Ni(dmg)₂] as a sacrificial template under nitrogen flow at different temperatures. The structure, morphology and properties of the products were characterised by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), N₂ adsorption–desorption measurements and ultraviolet-visible (UV-vis) spectrophotometry. The optimised Ni@NC-700 sample exhibited an excellent ability to reduce 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) by NaBH₄ in an aqueous solution, which shortened the reduction time to 3.0 min with a conversion of nearly 100%. In addition, Ni@NC-700 possessed magnetic properties, which provided efficient separation by an external magnetic field. The present report may provide a potential and favourable method for preparing magnetically reusable Ni NP anchored N-doped porous carbon catalysts derived from a simple coordination complex.