Controlling nanostructures of PtNiCo/C trimetallic nanocatalysts and relationship of structure-catalytic performance for selective hydrogenation of nitroarenes

•PtNiCo/C catalyst is acquired via ambient-temperature synthesis method.•PtNiCo nanostructures in PtNiCo/C-X are tuned by controlling its reduction temperature.•Relationship of structure-performance in PtNiCo/C-X for nitroarenes selective hydrogenation is established.•PtNiCo/C-200 shows much higher catalytic activity and selectivity (100%) to NO2 hydrogenation than PtNiCo/C-500 due to the synergy effect.