FeAtHEr-Cm update

Previously, I announced my latest project in The start of FeAtHEr-Cm. Over the past several weeks, I’ve been iterating through the potentiostat design and I think I’m at a point that the design will stay more or less in place, allowing me to shift my focus to documentation, instrument use and lesson plans.

I’ve also spent some time building a website that contains the documentation for building the instrument, writing code and using the potentiostat in an educational setting. Rather than re-write all of that information here, head on over to this page for a summary of what’s been done and what’s in the pipeline.

Example CVs from 0.01 to 0.5 V/s of potassium ferrocyanide in 0.1 M KCl at a 2 mm diameter Pt electrode. Obtained using the gamma version of the bob173 potentiostat.

It’s bath time at the grotto

It looks like the robin and grackle young have fledged. Today there is a marked uptick in bathing activity at the grotto. This youngster (a starling) has been dancing around the waterfall trying to find a spot where it can mimic the older birds. Robins and mature grackles dominate the two ideal bathing spots. The shaky, poor color video is due to me filming this with my SLR through the window.

The start of FeAtHEr-Cm

Today I did some electrochemistry.

A cyclic voltammogram

OK, that’s not too surprising from a person who earned is PhD doing electrochemistry; however this is different, and it has nothing to do with me avoiding cyclic voltammetry for the last decade of my career. It’s because I built this:

A potentiostat prototype, with electrochemical cell for scale.

That’s a bare-bones potentiostat built on top of the Adafruit Feather M4 Express and programmed using Circuitpython. There remains a lot of work to be done, but the fact that I could build a functioning scientific instrument for under $30 makes me think that this approach could make it possible one day to have a 1:1 student-to-instrument ratio when teaching voltammetry in analytical chemistry courses.

I’m thinking that it may be possible to build an entire suite of chemistry instrumentation based on the Feather platform, so I’m coining the phrase FeAtHEr-Cm for this project.