I have been doing exactly this recently. Though my CO2 sensor was 3.3V. But a solution could be powering the sensor with the VIN 5v pin and using a level shifter for communication. That's what I did with the 5V screen I used (though I didn't need a level shifter). I also added a lithium battery with a charging and safety circuit hooked up to a boost converter making it 5V and connected that with VIN and GND.

My lab partners think we should use the center of the 1st gaussian as the real peak, because the presence of the second peak influences the position of the first within the data as in, we aren't talking about the fitted-function, we are talking about the data points themselves.