▎ 摘　　要

Covalent functionalization of graphene nanoparticles by autoclave, reflux-condensation, and microwave-assisted methods was performed. Nanofluids prepared by acidic functionalized graphene exhibit a higher dispersion stability than raw graphene. The thermal conductivity of nanofluids obtained by the microwave-assisted method was higher than with other functionalization methods, and a signifcant maximum thermal conductivity enhancement compared to deionized water was achieved. Microwave-assisted thermochemical synthesis is a highly effective energy-saving method over other conventional approaches.