SDC Overview
The VersaSCAN SDC integrates the Base with a VersaSTAT, a PTFE machined head, and a peristaltic pump. The SDC technique confines the electrochemical measurement to the small droplet of electrolyte, defining the area of the electrode/electrolyte interface. SDC adds spatial resolution to applications such as kinetics, corrosion, fluid-flow studies, and any application where a small area on a sample needs to be investigated without cutting the sample or subjecting areas to different electrolyte exposure times.
-
Compatible Potentiostats: VersaSTAT 3 / 3F /4
-
Capable of running both constant bias/swept position plots for data maps and fixed-position/ dynamic signal plots for Cyclic Voltammetry, Tafel, EIS, etc.
-
Capable of running experiments with flowing or static drop of electrolyte.
Scanning Droplet System (SDC) uses a compact peristaltic pump to force electrolyte through a small diameter tube and into a specifically designed head. This PTFE-based SDC head is machined to allow electrolyte to flow past an installed Reference Electrode and then to a port at the base of the head.
When the head is positioned sufficiently close to the sample a droplet forms between the head and sample. Tubing is also connected to an output port of the PTFE head. A second channel of the same peristaltic pump is then used to draw electrolyte past an installed Counter Electrode and out of the system. SDC experiments can be configured to either:
- Apply a constant bias (potential, current or open (circuit) and increment position of the head creating a data map.
-
Apply a static or dynamic electrochemical signal, such as a EIS experiment, a Tafel plot, or a Cyclic Voltammetry experiment as the head is kept in a fixed location.
Since electrochemistry occurs at an electrode/electrolyte interface, only the portion of the sample that is in contact with the droplet is being measured. This allows experiments to study a small area of a large sample, without cutting the sample and thus limiting edge effects.
When running, the SDC pump creates a flowing droplet. SDC’s pump velocity can be tuned to study different effects of flow rate.
SDC Specifications
Potentiostats: | |
Compliance Voltage | ±12V |
Polarization Voltage | ±10V |
Current Ranges and Resolution | |
VersaSTAT 4 | 4nA to 1A standard; 120fA on 4nA range |
VersaSTAT 3F | 4nA to 650mA standard; 120fA on 4nA range |
VersaSTAT 3 | 200nA to 650 mA standard; 6pA on 200nA range |
SDC Head: | |
Material | PTFE |
Aperture | 500-micron diameter |
Reference Electrode | Ag/AgCl |
Counter Electrode | Pt wire |