title: From catalyst to classroom
title: developing fuel cell materials and electroanalytical tools
titleType: Subtitle
Creators: name: Coduto, Joshua R
Publisher: name: University of Iowa
Year: 2025
Subjects: subject: 3D Printing
subject: Catalysis
subject: Energy Systems
subject: Tafel Analysis
subject: public abstract
subject: Analytical Chemistry
subject: FOS: Chemical sciences
subject: Augmented Reality
subject: Electrochemistry

description: Fuel cells and electrolyzers are of significant interest for energy storage and energy generation. Fuel cells can provide power with minimized or eliminated greenhouse gas emissions, depending on the fuel and system design. The commercial appeal of fuel cells is limited in large part by low cost effectiveness. Though high in performance, platinum based catalysts are expensive and prone to poisoning during operation. This work discusses efforts to increase fuel cell cost effectiveness through the use of inexpensive, platinum free materials. Different fuel cell designs, electrochemical reactions, and catalyst materials are studied to assess changes in performance.
description: Electrochemistry and analytical chemistry are complex fields of study and can be difficult for researchers and students alike. Researchers from diverse backgrounds commonly employ electroanalytical techniques and principles. Analysis tools can make measurements more approachable for researchers without extensive training in electrochemical techniques. Similarly, underlying chemical principles can be made more approachable using contemporary technology. This work discusses the development and exploration of tools designed to improve electrochemical measurements and chemical understanding.
description: Tafel analysis is a widely used electrochemical technique. The measurement is used to assesss ystem and catalyst performance for energy systems, materials science, and corrosion. Classical Tafel analysis (CTA) is burdened by the subjective determination of linearity. Kinetic parameters obtained by linear regression may vary significantly with the chosen linear region. Continued use of CTA despite the presence of advanced Python libraries for electrochemical analysis conveys the need for more accessible tools. Taffit, an analysis tool to replace classical Tafel analysis is presented and benchmarked. The tool, Taffit, generates and fits Tafel plots from LSV data in Microsoft Excel®. The tool produces the exchange current density j0, charge transfer coefficient α, and Tafel slopes of closest fit. Comparisons between Taffit and CTA show increased precision for the presented tool in cases of both fast and slow kinetics. Agreement is also shown with values reported in the literature. The developed algorithm drastically reduces subjectivity and improves fundamental data analysis.
description: Previous research has reported magnetic effects on the Hydrogen Evolution Reaction(HER), showing significant improvements for measurements of current onset. However, greater understanding of interfacial kinetics is needed for validation of proposed magnetoelectrochemical mechanisms. Here, sensitive Tafel measurements are employed to develop a greater understanding of magnetic effects on hydrogen reduction. Ferrimagnetic particles of different dimensions, volume fractions, and coatings were embedded onto carbon surfaces. The presence of a magnetic field at the electrode surface produces a fivefold increase in the heterogeneous electron transferr ate constant. No change in Tafel slope is observed on magnetization, indicating a mechanism still limited by initial adsorption of hydrogen.
description: Oxygen is the most common oxidant used in fuel cell operation. The Oxygen Reduction Reaction is limited by sluggish kinetics and the requisite use of platinum group metal (PGM) catalysts. Select lanthanides in organic solvents have previously shown enhancement of ORR kinetics. Extension of the study to aqueous media would better reflect most fuel cell conditions. Here, different lanthanide species are deposited at both bare and Nafion modified glassy carbon electrodes. Select modifications, principally those containing Yb and La, show improvements in ORR performance in Nafion composites. Bare electrodes with deposited lanthanides show poor performance, indicating the formation of insulating films with unfettered access to the electrode surface. Indirect electrochemical deposition and surface embedded lanthanide salts show differing electrochemical performances. Magnetic effects on ORR are also reported, showing enhancement in both overpotential and peak current densities.
description: Ethanol is of interest as an electrochemical energy source for its comparatively low greenhouse emissions and safety hazards. 3D printed direct ethanol fuel cells (DEFCs) are studied as an unexplored technique in energy storage research. 3D printing of fuel cell components stand to improve customizability and uniformity of electrode surfaces. Catalysts can be directly added to custom filaments, embedded via solubilization, or electrodeposited to the electrode surface. Conductive composite filaments have been previously explored for their electrochemical properties, showing adequate conductivity and performance for benchmark redox reactions. 3D printed electrodes have not been utilized for practical purposes in energy storage. Here, several filament types, catalyst materials, and fuel delivery mechanisms are explored for their effects on an experimental 3D printed stack design. Results show promise for 3D designs, with power levels comparable with microbial fuel cells. Enhancement in cell performance is observed for magnetically enhanced electrodes, and a vapor ethanol feed shows promise as a method for minimizing fuel crossover.
description: Chemistry undergraduates regularly mentally construct and manipulate 3D information. Facile manipulation of 3D information can help students succeed in chemistry, while poor spatial ability can hinder performance. Structure, symmetry, and lattices have been the primary focus for accommodating differences in spatial ability. However, electrochemistry and analytical chemistry regularly deal with 3D graphical information. Augmented reality (AR) and 3D viewing technology are promising tools for visualization in educational settings. Here, 3D objects pertaining to electroanalytical chemistry are created and implemented into an analytical chemistry classroom. Results show generally favorable student opinion, with the need for careful course scaffolding and heavy annotation of complex 3D objects. The technology shows great utility in displaying complex equilibria, graphical data, and concepts related to analytical chemistry.