Controllable growth of gold nanowires and nanoactuators via high-frequency AC electrodeposition

An electrochemical deposition method using high-frequency alternating current (AC) signal is reported here for the in situ synthesis and assembly of Au nanowires and nanoactuators on microelectrodes without using any masks or templates. High conductivity of 3.79 ± 0.14 × 107 Ω− 1 m− 1 is achieved on the Au nanowires assembled between electrodes. Au nanoactuators with expansion ratio of more than 500% can be fabricated at higher frequency. The actuators can act as claws to grab SiO2 nanoparticles in a water solution when driven by an alternating electric field. Disconnected nanowires and nanoparticles which self-aligned around the electrodes were also obtained at lower gold ion concentration, indicating a different current transfer mode in AC electrodeposition.

► A high-frequency AC electrodeposition method was developed to synthesize Au nanowires and nanoactuators controllably.
► Au nanowires with conductivity of 3.79 ± 0.14 × 107 Ω-1m-1 were synthesized in situ and self-assembled on microelectrodes.
► Au nanoactuators were synthesized which can grab SiO2 nanoparticles in a water solution when driven by an AC field.