Electrochemical Scanning Probe Microscopy: Increased Control for MultiMode AFMs

The MultiMode^® Atomic Force Microscopes (AFMs) systems from Bruker are the most productive electrochemical (EC) systems that are commercially available today, with more peer-reviewed EC publications than any other commercial AFM. Three powerful options are available with Bruker for performing electrochemical (EC) scanning probe microscopy: Electrochemical Scanning Tunneling Microscopy (ECSTM), Electrochemical Atomic Force Microscopy (ECAFM), and Scanning Electrochemical Potential Microscopy (SECPM).

Bruker’s ECAFM module, together with the in-built electrochemistry/SPM software, provides researchers the flexibility, spatial resolution, and ease of use to analyze an extensive range of in-situ, real-time electrochemical processes, from UPD and adsorption/desorption to corrosion and electroplating. Each option includes a galvanostat/bipotentiostat, liquid and electrode attachments, one or more liquid cells and can be bought as a full system on a new MultiMode 8-HR or as an add-on to a current MultiMode system.

MultiMode EC modules enable

• Bipotentiostat control over a large current-sensing range, from 0.1 nA to 100 mA
• SECPM for probable profiling of electrical double layer and in-situ imaging or prospective mapping at nanoscale resolution
• Electrochemistry control of the atmosphere above fluid cells to stop reactivity between fluid and sample due to gaseous environments

Bruker’s SECPM solution includes a bipotentiostat/galvanostat, liquid cell, and attachment.

Scanning Electrochemical Potential Microscopy (SECPM)

Bruker’s exclusive SECPM is a patented method that provides potential mapping or in-situ imaging of the electrode surface with nanometer-scale resolution. The electrochemical potential is dynamic with distance across the electrical double layer at solid/liquid interfaces. SECPM measures the potential difference between its potentiometric probe and the sample in a polar liquid or an electrolyte solution. Furthermore, scanning tunneling microscopy (STM) is combined with SECPM, providing integrated flexibility, power and comparison of images and data captured with the two methods. SECPM includes a galvanostat/bipotentiostat, liquid cell and attachments.

Electrochemical Scanning Tunneling Microscopy (ECSTM)

ECSTM facilitates real-time in-situ STM imaging with atomic and molecular resolution of the electrode surface in solution under electrochemical regulation. ECSTM comprises of a galvanostat/bipotentiostat, liquid cell and attachments.

Electrochemical Atomic Force Microscope (ECAFM)

ECAFM facilitates real-time in-situ AFM imaging with nanometer resolution of the electrode surface in solution under electrochemical regulation. ECAFM includes a galvanostat/bipotentiostat, liquid cell and attachments.

Bipotentiostat/Galvanostat

Bruker’s bipotentiostat helps researchers to regulate electrochemical processes either galvanostatically or potentiostatically. Electrochemical control and data acquisition is combined into the NanoScope^® SPM software. Electrochemical and topographical data are recorded at the same time, thus correlation of the two is immediately available. Alternatively, an external potentiostat can be used.

Accessories/Options

• Fluid Imaging Cells
• Signal Access Modules
• Temperature Accessories
• Electrochemistry STM/AFM Converter
• Electronic and Thermal Applications Modules
• STM and Low-Current STM Converters

STM images of Pt(111) electrode in 0.1 mM KCN + 0.1 M KCIO₄ taken at 0.6 V vs. RHE. (A) was taken 20 seconds before image (B). 30 nm scans.

In-situ 20-nm STM scan (A), and zoom (B) of (√3×√3)R30 adlayer structure formed by underpotential deposition (UPD) of a sub-monolayer of Cu on Au(111)/mica in 0.1 M H₂ SO₄ + 5 mM CuSO₄ at -105 mV vs. Ag/AgCl. Arrows locate four atomic point defects.

In-situ AFM image of overpotential deposition of Cd on Cu(111) surface obtained in the solution containing 2 mM Cd(CIO₄)₂ + 0.1 M HCIO₄ at -580 mV vs. NHE. 650 nm.