We　present　a　facile　one-step　synthesis　of　chemically　stable　and　magnetic　Co@BN　core-shell　nanoparticles.　We　found　that　Co@BN　nanoparticles　acted　as　excellent　catalysts　with　high　stability　and　magnetic　recyclability　for　reduction　of　nitroarenes　to　aminoarenes　under　mild　reaction　conditions.　The　sample　13.6　wt%　Co@BN　showed　the　best　catalytic　activity　for　reduction　of　4-nitrophenol　(4-NP).　In　addition,　a　significant　synergistic　effect　of　the　h-BN　support　was　observed　during　the　catalytic　reaction　by　effectively　adsorbing/concentrating　and　ionizing　the　reactant　nitroaromatics.　Moreover,　the　kinetics　of　the　catalytic　reaction　were　investigated　at　different　reaction　temperatures,　4-nitrophenol　concentrations,　sodium　borohydride　concentrations,　metal　loadings　and　catalyst　amounts.　The　activation　energy　of　the　catalytic　reduction　of　4-nitrophenol　for　13.6　wt%　Co@BN　was　determined　to　be　102.93　kJ　mol-1.　This　work　provides　a　clear　example　of　Co@BN　core-shell　nanoparticles　as　nanocatalysts.　©　2017　The　Royal　Society　of　Chemistry.