Template-directed synthesis of hierarchically mesporous superparamagnetic carbon-coated nickel nanoplates

• A facile and controllable method for synthesizing Ni@C nanoplates has been proposed.
• A novel, hierarchically mesporous Ni@C core–shell nanoplates has been prepared.
• Ni@C nanoplates will be a candidate for magnetic separation and catalysts materials.

This paper reports the preparation of carbon-coated nickel (Ni@C) nanoplates through an extension of stöber method and subsequent calcinating approach, in which Ni(OH)2 nanoplates were chosen as the templates. The obtained Ni@C nanoplates exhibit a uniform hexagonal core–shell structure with a size of 140 nm and a thickness of 20 nm shell. Ni@C nanoplates possess a high specific surface area and a hierarchical mesoporous structure (pores located in 3 nm and 50 nm). The magnetic hysteresis curve reveals that Ni@C nanoplates have a certain degree of magnetism with near-zero coercivities and low remanence, indicating superparamagnetic performance. Ni@C nanoplates own a promising potential for a magnetic catalyst.