Microwave-assisted activation for electroless nickel plating on PMMA microspheres

► Microwave-assisted activation method for electroless plating.► Pd with a size of 4–6 nm uniformly distributed on the surfaces of the PMMA microspheres.► Nickel–phosphorus alloy coating on the PMMA microspheres. A novel microwave-assisted activation method for electroless plating on PMMA microspheres is presented in this study. When the microwave irradiation was applied during the activation step, the amount of the Pd species adsorbed on PMMA surfaces was much higher than that of sample pretreated with a conventional activation process without microwave irradiation. With this activation method, it was also shown that the adsorbed Pd species with a size of 4–6 nm were uniformly distributed on the surfaces of the PMMA microspheres, thus a smooth and uniform nickel–phosphorus coating on the PMMA microspheres was obtained by subsequent electroless plating. The samples after each step were characterized by XPS, TEM, ICP and SEM.