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This paper presents a teaching kit that combines the fabrication of a low-cost microcontroller-based potentiostat and a LabVIEW-generated graphical user interface. The potentiostat enables undergraduate-level students to learn electroanalytical techniques and characterize energy conversion devices such as solar cells. The purpose of this teaching module is to make the introduction of electrochemistry accessible to undergraduate laboratories, especially those with limited financial resources and without expertise in electronics or programming. The electronic circuit components for the potentiostat are readily available and easy to assemble. The graphical user interface replaces any programming-based interface, displays data in real time, and interacts with user commands. The software package is a stand-alone executable file that is compatible with any PC and is provided in the Supporting Information. Cyclic voltammetry, linear sweep voltammetry, and chronoamperometry functions are demonstrated with representative electrochemical experiments, and the data obtained are comparable to those obtained with a research-grade potentiostat. This teaching module is user-friendly so that it can be easily adapted into the undergraduate classroom. We make available in the Supporting Information all of the necessary instructions and information, including schematics for the potentiostat, circuit layout, electronic components, case fabrication, step-by-step instructions for assembly, software user interface, and detailed operating instructions.

In order to enable students who are blind and visually impaired to observe chemical changes in solutions, a hand-held device was designed to output light intensity as an audible tone. The submersible audible light sensor (SALS) creates an audio signal by which one can observe reactions in a solution in real time, using standard laboratory glassware such as test tubes or beakers. Because many observations in the chemistry laboratory are visual, the SALS device enables students who are blind and visually impaired to perform a broader range of experiments independently. It is believed that this active participation will inspire more of these students to pursue careers in the science, technology, engineering, and mathematics (STEM) professions. The SALS device can be further refined to provide vibratory and visual outputs for students with learning or physical disabilities. (Contains 3 figures.)

The teaching of instrumental analysis for many small colleges and high schools continues to be stymied by high-cost, complicated maintenance, high power requirements, and often the sheer bulk of the instrumentation. Such issues have led us to develop inexpensive instruments as part of a SMILE initiative (small, mobile instruments for laboratory enhancement). This lab-based pedagogy, primarily aimed at engaging science and engineering students, has shown to significantly enhance the confidence and achievement of students in our technology-based courses. One instrument that has been designed, constructed, and characterized is the cyclic voltammeter (CV). CV is a versatile electroanalytical technique that monitors the redox behavior of chemical and biochemical species in solution. The CV instrument and technique readily lends itself to miniaturization and facilitates the practical application of CV analysis within standard undergraduate and advanced high school laboratory courses. The entire instrument was constructed for less than $50, thus allowing deployment of multiple apparatus in laboratories with a modest budget. Less noisy data was obtained when a commercial Pt working electrode was used, taking the total cost to less than $250. Together with details on how to construct the instrument, a series of experiments for the student-built CV have been described.