High-aspect ratio needle probes for combined scanning electrochemical microscopy — Atomic force microscopy

The development and characterisation of high-aspect ratio needle probes for combined scanning electrochemical microscopy–atomic force microscopy (SECM–AFM) is described. Commercially available coated metallic needle probes have been modified by a simple procedure to yield probes with an addressable nano-disk electrode integrated into the tip apex. The probes behaved well electrochemically, with a typical electrochemical radius of approximately 140 nm and the preliminary application of these probes to high-resolution topographical and electrochemical imaging was demonstrated.