Amino acid-assisted synthesis of porous graphitic carbon spheres with highly dispersed Ni nanoparticles

Abstract

An easy and facile method is proposed for achieving uniform dispersion of small-sized nickel nanoparticles in carbon spheres. The sintering of metal nanoparticles commonly observed during thermal treatment in the post-synthetic impregnation is significantly reduced by using one-pot Stöber synthesis in the presence of an amino acid. The formation of complexes between amino acids and nickel ions not only improves the distribution of nickel nanoparticles but also retains the spherical morphology of carbon spheres. The incorporated nickel nanoparticles facilitate the formation of graphitic domains in carbon spheres at relatively low temperature and meantime introduce mesoporosity as evidenced by nitrogen adsorption-desorption isotherms, XRD and TEM analysis. The in-situ reduction of Ni ions into metallic nickel is afforded by carbon that eliminates the need of extra step and additional cost of using a reducing agent for the synthesis of nickel-incorporated carbon spheres either as magnetically separable adsorbents or for catalytic and energy-related applications. This method provides spherical carbons with unique properties such as graphitic nature, highly dispersed metallic nickel nanoparticles, and mesoporous structure.