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Published March 3, 2017 | public
Journal Article

Atomic force microscopy with nanoelectrode tips for high resolution electrochemical, nanoadhesion and nanoelectrical imaging

Abstract

Multimodal nano-imaging in electrochemical environments is important across many areas of science and technology. Here, scanning electrochemical microscopy (SECM) using an atomic force microscope (AFM) platform with a nanoelectrode probe is reported. In combination with PeakForce tapping AFM mode, the simultaneous characterization of surface topography, quantitative nanomechanics, nanoelectronic properties, and electrochemical activity is demonstrated. The nanoelectrode probe is coated with dielectric materials and has an exposed conical Pt tip apex of ~200 nm in height and of ~25 nm in end-tip radius. These characteristic dimensions permit sub-100 nm spatial resolution for electrochemical imaging. With this nanoelectrode probe we have extended AFM-based nanoelectrical measurements to liquid environments. Experimental data and numerical simulations are used to understand the response of the nanoelectrode probe. With PeakForce SECM, we successfully characterized a surface defect on a highly-oriented pyrolytic graphite electrode showing correlated topographical, electrochemical and nanomechanical information at the highest AFM-SECM resolution. The SECM nanoelectrode also enabled the measurement of heterogeneous electrical conductivity of electrode surfaces in liquid. These studies extend the basic understanding of heterogeneity on graphite/graphene surfaces for electrochemical applications.

Additional Information

© 2017 IOP Publishing Ltd. Received 14 November 2016, revised 6 January 2017; Accepted for publication 10 January 2017; Published 31 January 2017. ZH, RP, and CL (employed by Bruker) developed the technique, manufactured the nanoelectrode probe, fabricated the Pt/nitride sample, and were involved in most of the measurements in collaboration with the other authors. Results collected on HOPG and the mesh electrodes were primarily performed by SWB and MRN. SWB, MRN, and ZH led manuscript preparation. SWB and MRN acknowledge support by the Department of Energy, Basic Energy Sciences, award number DE-SC0014279. The modeling and simulation work, and some of the SEM imaging were performed by YC, JJ and CX, and were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993. GP, MR, AM, SG and CS performed the preparation of and measurements on the Au nanomesh electrode, and acknowledge the support from the German Research Foundation (DFG) in the framework of the Collaborative Research Center (SFB 840). CS acknowledges support from the Elite Network of Bavaria (ENB). BSB acknowledges support from the National Science Foundation (NSF) Center for Chemical Innovation in Solar Fuels (CHE-1305124) for research (probe testing and device evaluation) carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. RK assisted in the test of chemical compatibility and the PF-TUNA in liquid measurement.

Additional details

Created:
August 19, 2023
Modified:
October 24, 2023