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

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.