Hello everyone! I am new to hardware/electronics and I would like to create a Redox electrochemical sensor using Arduino Uno. I cannot use any pre assembled circuits, and I have to construct the two electrodes myself. Do you have any suggestions / valid references for me to begin with? Thanks in advance!
well - for a start you'll need two electrodes, one for the anode (oxidation) and one for the cathode (reduction).
If you are rich, you can use platinum or gold for the electrodes but carbon is also a good choice. if there is an archery range near you, go check if they have leftovers from broken arrows. Many of those are made of carbon those days and you can use that as a rod
then you need the electrolyte solution. Simple solutions of salts like sodium chloride (NaCl) will get you started.
Please ensure electrodes don't touch each other and apply a stable reference voltage to one electrode while measuring the potential difference with the other one using an analog pin (or a better ACD) to extract the Redox Potential (and with proper calibration and the use of Nernst equation you can estimate the concentrations of specific chemical species involved in the redox.
have fun
Aren't those typically insanely high input impedance circuits? To the point where you need to use Teflon insulators because PVC is too conductive?
Creating a Redox (ORP) sensor from scratch can be a bit challenging, but it's definitely possible with the right components and knowledge. In this answer, I'll provide a high-level overview of the process, but please note that this is a complex project and might require some experience in electronics and chemistry.
Components You'll Need:
- Electrodes: You'll need two electrodes - a working electrode (WE) and a reference electrode (RE). Platinum or gold electrodes are commonly used for the working electrode, and Ag/AgCl is often used for the reference electrode.
- Electrolyte: You'll need an electrolyte solution to immerse your electrodes in. The choice of electrolyte depends on the specific application.
- Op-Amp Circuit: You'll need an operational amplifier (op-amp) circuit to measure the potential difference (voltage) between the working and reference electrodes. This circuit will amplify the small voltage generated by the electrochemical reactions.
- Arduino Uno: You'll use the Arduino Uno to read and process the voltage signal from the op-amp circuit.
- Calibration Solutions: You'll need calibration solutions of known ORP values to calibrate your sensor.
Steps to Create the Redox Sensor:
- Prepare Electrodes: Construct your working and reference electrodes. For a simple setup, you can use platinum wire for the working electrode and Ag/AgCl for the reference electrode. Make sure they are properly cleaned and polished.
- Assemble the Electrochemical Cell: Create an electrochemical cell by immersing the electrodes in the electrolyte solution. The working electrode should be immersed in the solution where you want to measure the ORP, and the reference electrode should be immersed in a separate container with the same electrolyte solution.
- Op-Amp Circuit: Design and build an op-amp circuit to measure the potential difference between the working and reference electrodes. The op-amp should be configured in a way that it provides a readable voltage output to the Arduino. The exact circuit design will depend on your specific setup.
- Calibration: Calibrate your sensor using ORP standard solutions. Measure the voltage output of your sensor for each standard solution and create a calibration curve to relate voltage to ORP.
- Connect to Arduino: Connect the output of your op-amp circuit to one of the analog input pins on the Arduino Uno. Write a Arduino sketch to read the voltage value and convert it to ORP values using the calibration curve.
- Data Logging/Display: Depending on your project requirements, you can either log the ORP data to a storage medium or display it on a screen.
- Testing: Thoroughly test your sensor under different conditions to ensure its accuracy and reliability.
Remember that the details of your circuit and sensor will depend on your specific requirements and the chemicals involved, so it's essential to research and potentially consult with experts in electrochemistry for your specific application. Safety precautions should also be taken when working with chemicals and electrical components.
Why the chatGPT copy paste ?
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