Publications
Showing 36 results for Author: Shawn K. Reeves
Aug, 2026
Journal
Evaluating the Effects of Anode Porous Transport Layer on the Performance and Durability of Anion Exchange Membrane Electrolyzers
As anion exchange membrane systems have emerged as a competitive low temperature electrolysis technology, research has expanded to other components and device integration. In this study, nickel (Ni) and stainless steel (SS)-based porous transport layers (PTLs) are investigated in membrane electrode assemblies (MEAs). Compared to MEAs using Ni, the SS PTL shows higher perfo…
Jul, 2026
Journal
Understanding Discharge-Driven Growth of Cathode Impedance in Ni-Rich NMC Cathodes
Degradation of LiNixMnyCo1-x-yO2 (NMC)-based lithium-ion batteries depends strongly on cut-off voltage ranges. In addition to the high upper cut-off voltage, a high depth of discharge (i.e., lower cut-off voltage) significantly worsens cathode impedance growth and capacity fade during long-term cycling. However, there is currently no consensus on the mechanism behind the n…
May, 2026
Journal
Durable Thin-Film Porous Transport Electrodes for High Current Density PEM Water Electrolysis
Proton exchange membrane water electrolyzers rely on relatively expensive Ir-based catalysts for efficient and durable hydrogen production. To reduce system costs, Ir loadings can be reduced if performance and durability are maintained. Sputter deposition is a readily scalable method to synthesize uniform, low-loading catalyst layers with controlled composition. A catalyst…
May, 2026
Journal
Rational Design of Weakly-Solvating Molecules for Salt-In-Pre-Ionic-Liquid Electrolytes for Li Metal Batteries
Lithium metal batteries (LMBs) promise step-changes in energy densities but suffer from poor cycle life due to unstable electrolyte-lithium interfaces. Conventional carbonate electrolytes exhibit excessive lithium-ion solvation and low oxidative stability, leading to rapid capacity loss. Herein, we report a rationally designed weakly-solvating cyclic sulfonamide, 1-trifluo…
May, 2026
Journal
An Acid-Free, Temperature-Based Cation Contamination Removal Strategy for PEM Water Electrolysis
It is widely understood that the durability and reliability of polymer electrolyte membrane (PEM) water electrolyzers are heavily dependent on feedwater purity, with cation contaminants that originate from incomplete water purification and balance of plant materials significantly harming electrolyzer performance. However, contamination remains a challenge and a common caus…
Apr, 2026
Journal
How Selective Transport Layer Improves Efficiency and Durability of Proton Exchange Membrane Fuel Cells
In any electrochemical device, the separator or membrane allows specific ions to transport but blocks electrons and other chemical species, enabling the electrochemical energy to be harvested. However, small amounts of undesired species are known to permeate through the membrane, reducing overall system efficiency and lifetime. An emerging concept called the “Selective Tra…
Jan, 2026
Journal
The Impact of Catalyst Layer Composition and Structure on Performance and Durability of PEMWE Anodes
A study of various compositions of anodes for proton exchange membrane water electrolysis aimed at reducing precious metal content and system costs without compromising performance and durability is presented. A key challenge in current water electrolysis technologies is the reliance on high iridium loadings to ensure sufficient catalytic activity, electronic conductivity,…
Jul, 2025
Journal
The Impact of Membrane Inactive Area on the Durability of Pt-Co Catalyst
Platinum (Pt) is the most active catalyst for oxygen reduction reaction; however, its activity still requires a significant increase to meet the demands of practical applications. To enhance the catalytic activity, alloy catalysts like platinum-cobalt (Pt-Co), are being extensively investigated. However, Co leaching from the Pt-Co alloy remains a significant concern. Evalu…
Jan, 2025
Journal
Identifying electrochemical processes by distribution of relaxation times in proton exchange membrane electrolyzers
Distribution of relaxation time (DRT) is used to interpret electrochemical impedance spectroscopy (EIS) for proton exchange membrane (PEM) water electrolyzers, with an attempt to separate overlapped relaxation processes in Nyquist plots. By varying operating conditions and catalyst loadings, four main relaxation peaks arising from EIS can be identified and successfully sep…
Aug, 2024
Journal
Simulated Start-Stop and the Impact of Catalyst Layer Redox on Degradation and Performance Loss in Low-Temperature Electrolysis
Stress tests are developed that focus on anode catalyst layer degradation in proton exchange membrane electrolysis due to simulated start-stop operation. Ex situ testing indicates that repeated redox cycling accelerates catalyst dissolution, due to near-surface reduction and the higher dissolution kinetics of metals when cycling to high potentials. Similar results occur in…