Metal-coated microcapsules with tunable magnetic properties synthesized via electroless plating

•Metal-coated microcapsules with tunable magnetic properties was developed.•Magnetic properties were changed by varying pH condition of electroless plating.•Prepared microcapsules showed magnetic responsivity under external magnetic field.

Metal-coated microcapsules with tunable magnetic properties, which contained liquid cores and metallic Ni-P alloy shells, were synthesized via electroless plating. The fabrication process consisted of emulsification, phase separation, and electroless Ni plating stages. The material composition and sizes of Ni single crystals in the obtained metallic shells depended on the pH of the plating solution. It was found that the microcapsules prepared at high pH values (8.0 and 10.0) were characterized by ferromagnetic properties, whereas those synthesized at low pH values (4.7 and 6.0) were superparamagnetic. The produced microcapsules have potential applications as magnetic responsive carriers of phase change materials, which can be easily transferred to a desired place by applying external magnetic field.