Spring 2021 Shires Graduate Seminar Series

Date/Time
Date(s) - Fri 02/26/21
1:30 pm - 2:20 pm

Location
Zoom ID to be provided by email

Categories


Enhancing performance in the NASA Air Quality Monitor (AQM) through thermoelectric cooling of gas chromatograph (GC)

Peter Fowler, Ph D Candidate in CHME

A crucial task for human use of the International Space Station is establishing and maintaining a human suitable atmosphere for breathing. Due to the generation and recirculation technology necessary on spacecraft, there is a need for strict monitoring of air quality through detection of key chemicals of concern to human health and safety. The current technology used for this purpose is a Gas Chromatograph-Differential Mobility Spectrometer (GC-DMS) instrument, chosen for its robust, low-power, portable construction and high sensitivity. However, co-elution of some volatile organic compounds (VOCs) in the GC stage complicates measurements and determination of key compounds of interest to NASA in the ISS. Consequently, for the 22 compounds monitored in the air two separate GC columns with different stationary phase composition are needed, with two specialized instruments tuned for subsets of the chemicals they measure. Through addition of a thermoelectric cooler for the GC column, separation of VOCs of interest is achieved by cooling the GC to sub-ambient temperatures. Properly integrated, this modification would lead to a single instrument which could separate, quantitate, and identify all 22 chemicals, upgrading the AQM for use in future spaceflight programs.

Bio: Born in Honduras and raised in Montana, Peter came to NMSU for an undergraduate degree in Engineering Physics and stayed for a PhD in Chemical Engineering with Dr. Rockstraw as his advisor, and Dr. Eiceman as co-advisor in Chemistry. He enjoys the culture and feel of the borderland and has found a place in the field of chemical and process instrumentation, on which he is involved in ongoing research with NSF and NASA alongside the research for his PhD.

Understanding of A-site Deficiency in Layered Perovskites: Promotion of Dual Reaction Kinetics for Water Oxidation and Oxygen Reduction in Protonic Ceramic Electrochemical Cells

Wei Tang, Ph D Candidate in CHME

Protonic ceramic electrochemical cells (PCECs) are a promising solid-state energy conversion device which enables conversion of energy between electricity and hydrogen at intermediate temperatures. Rapid conversion between chemical and electrical energy via PCEC technology will assist in meeting the grand energy storage challenge. However, PCECs operations in fuel cell mode and electrolysis mode are limited by their oxygen electrode due to the high activation energy and sluggish kinetics for oxygen reduction reaction (ORR) and water oxidation reaction (WOR) of traditional oxygen electrode materials, respectively. In this work, we developed a novel oxygen electrode by introducing A-site deficiency in layered perovskite to boost WOR and ORR activities while maintaining the durable operation. The introduction of cation deficiency results in higher oxygen vacancies at operation temperature and hence boost its oxygen diffusivity and surface activity which was confirmed. When incorporated in PCECs, an improved performance in both fuel cell mode and electrolysis mode is obtained and dynamic reversible operation is achieved.

Bio: Wei Tang is a chemical engineering Ph.D. student working with Dr. Hongmei Luo in the Department of Chemical and Materials Engineering at NMSU. Wei came to NMSU in 2018 summer. During the first year in NMSU, he worked on electrocatalyst for hydrogen evolution reaction. Wei joined the Biological and Chemical Science and Engineering Department in Idaho National Laboratory (INL) as an intern in 2019 summer. Now he is focusing on the energy conversion and storage by protonic ceramic electrochemical cells.