Presentation on theme: "Team Members: Kyle Bloomer Josh Geiman Lucas Bennett Team Sponsor: Dr. Cindy Harnett Team Mentor: Dr. Andy Dozier."— Presentation transcript:
Team Members: Kyle Bloomer Josh Geiman Lucas Bennett Team Sponsor: Dr. Cindy Harnett Team Mentor: Dr. Andy Dozier
Dr. Harnett's laboratory needs 15 potentiostats for her microfluidics lab Off the shelf potentiostats range in price from $5K to $10K, which is prohibitive for an instructional lab Commercial Potentiostat
A Potentiostat is the electronic hardware required to control a three electrode cell and run most electro- analytical experiments. An electronic instrument that controls the voltage difference between a Working Electrode and a Reference Electrode. It measures the current flow between the Working and Counter Electrodes.
A previous potentiostat was attempted by a project team using an open source design, the Ardustat Hardware used was an Arduino processor board, with a prototype “daughter board” The Ardustat was a two electrode configuration Ardustat electrical design was poorly documented, which caused the project team to have difficulty implementing it for the project Software design had no documentation or comments for either the firmware or the application software The team was unable to meet the project goals
We have found an open source, three electrode potentiostat, known as the “Cheapstat” Cheapstat was developed by UC Santa Barbara to provide an affordable alternative to COTS potentiostats
Input parameters must be set through an onboard LCD and 5-way joystick The display is very limited ◦ LCD on the Cheapstat processor “box” Provides multiple measurement modes ◦ Square Wave ◦ Linear Sweep ◦ Stripping ◦ Cyclic Voltammetry
Front PanelPCB Assembly Joystick To Cell Electrodes
Two Electrode Potentiostat (Formally known as the “Ardustat”) Three Electrode Potentiostat (Formally known as the “Cheapstat”) Our project will entail the completion of both systems and comparison of test results of both systems.
Characterize electrical performance for a typical electrochemical device Compare electrical measurements between the two systems Two electrode vs. three electrode measurement differences Document all materials
Design and implement a three electrode potentiostat, based on the Cheapstat Three electrode design Ease of assembly and use by students, faculty, and staff PCB assembly techniques USB processor to PC interface External power sources Full documentation of hardware Schematics Simulation results Assembly diagrams List of Materials
Capture the test configuration Measurements to be made, ranges, etc. Execute the test using the measurements that have been established by the operator Log and time stamp test results in NVRAM Send measurement data to Display/Data Management System (DDMS) during test When polled by the DDMS, send the test results in CSV format to a file on the PC
Develop GUI and firmware using modern software engineering techniques No spaghetti code Comment all code Provide a software library Document all the application software and firmware Installation notes User’s Manual
Prepare four orange juice samples, one as a control, the other three containing the addition of exogenous ascorbic acid at 0.1,.02, and 0.3M respectively. Prepare a working electrode using a graphite pencil “lead”. Prepare a reference electrode using a standard Ag/AgCl electrode. Prepare a counter electrode using a piece of platinum wiring. (This will not be used for the Two Electrode Potentiostat configuration)
Attach the electrodes to the Potentiostat systems. Perform a cyclic voltammetry test taken from 200 to 900 mV, with a constant current of 550 mV. Export the data to CSV file and graph the results. Analyze graphed results against Rowe’s results using an eye inspection test.
Although the tests show that both systems work, the results were not as expected Several possibilities: ◦ Ag/AgCl reference electrode ◦ Relay usage ◦ Firmware implementation(?) ◦ Chemical procedure integrity
Universal System ◦ Verify suggested conclusion and recommendations Two Electrode Potentiostat ◦ Other modes of operation ◦ Calibration settings Three Electrode Potentiostat ◦ Implement DDMS GUI Removed joystick and LCD