Assistant Professor, McAuley Scholar | Chemistry
Dr. Arruda has a B.S. in Chemistry from the University of Massachusetts Dartmouth and a Ph.D. in Chemistry from Northeastern University, and completed a postdoctoral research fellowship at the Center for Nanophase Materials Sciences at Oak Ridge National Laboratory in Tennessee. He joined the faculty at Salve Regina University in 2013 where he teaches a host of chemistry and core curriculum courses.
Dr. Arruda’s interest in alternative energy began as an undergraduate researcher when he worked on electrochemical energy for propulsion systems as the Naval Undersea Warfare Center in Newport, RI. Following his work at NUWC, Dr. Arruda’s interest in energy evolved into more Earth-friendly renewable energy systems to mitigate the effects of climate change. He has worked extensively on understanding the role of catalysts in proton exchange membrane fuel cells, and more recently, has become interested in large scale energy storage systems for harnessing energy from intermittent sources such as wind and solar and currently conducts research on all vanadium redox flow batteries with Salve Regina University students. As a member of the Mercy Interdisciplinary Faculty Collaborative, a portion of Dr. Arruda’s research is supported by the McAuley Institute for Mercy Education: Critical Concern of Earth at Salve Regina University.
Wyndom S. Chace, Sophia M. Tiano, Thomas M. Arruda, and Jamie S. Lawton
Abstract: The VO2+/VO2+ redox couple commonly employed on the positive terminal of the all-vanadium redox flow battery was investigated at various states of charge (SOC) and H2SO4 supporting electrolyte concentrations. Electron paramagnetic resonance was used to investigate the VO2+ concentration and translational and rotational diﬀusion coeﬃcient (DT, DR) in both bulk solution and Nafion membranes. Values of DT and DR were relatively unaﬀected by SOC and on the order of 10−10 m2s−1. Cyclic voltammetry measurements revealed that no significant changes to the redox mechanism were observed as the state of charge increased; however, the mechanism does appear to be aﬀected by H2SO4 concentration. Electron transfer rate (k0) increased by an order of magnitude (10−6 ms−1 to 10−8 ms−1) for each H2SO4 concentrations investigated (1, 3 and 5 M). Analysis of cyclic voltammetry switching currents suggests that the technique might be suitable for fast determination of state of charge if the system is well calibrated. Membrane uptake and permeability measurements show that vanadium absorption and crossover is more dependent on both acid and vanadium concentration than state of charge. Vanadium diﬀusion in the membrane is about an order of magnitude slower (~10−11 m2s−1) than in solution (~10−10 m2s−1).
Chace, W.S.; Tiano, S.M.; Arruda, T.M.; Lawton, J.S. Effects of State of Charge on the Physical Characteristics of V(IV)/V(V) Electrolytes and Membrane for the All Vanadium Flow Battery. Batteries 2020, 6, 49, 1-16.
Open Access: DOI 10.3390/batteries6040049
Jamie S. Lawton, Sophia M. Tiano, Daniel J. Donnelly, Sean P. Flanagan, and Thomas M. Arruda
Abstract: The effects of sulfuric acid concentration in VO2+ solutions were investigated via electrochemical methods and electron paramagnetic resonance. The viscosity of solutions were independently measured via electrochemical methods and electron paramagnetic resonance (EPR), with excellent agreement between the techniques employed and literature values. Analysis of cyclical voltammograms suggest the oxidation of VO2+ to VO2+ is quasi-reversible at high H2SO4 concentrations (>5 mol/L), and approaching irreversible at lower H2SO4 facilities the electrochemical step but hinders the chemical step. Fundamental insights of VO2+/H2SO4 solutions can lead to a more comprehensive understanding of the concentration effects in electrolyte solutions.
Lawton, J.S.; Tiano, S.M.; Donnelly, D.J.; Flanagan, S.P.; Arruda, T.M. The Effect of Sulfuric Acid Concentration on the Physical and Electrochemical Properties of Vanadyl Solutions. Batteries 2018, 4, 40.
Open Access: DOI 10.3390/batteries4030040