KSEA events Unveiling the mechanism of phase evolution and H2 storage/CO2 uptake properties in nanohybride of magnesium borohydride supported by reduced graphene oxide (200124 KSEA Berkeley Chapter Seminar)
TITLE: Unveiling the mechanism of phase evolution and H2 storage/CO2 uptake properties in nanohybride of magnesium borohydride supported by reduced graphene oxide
SPEAKER: Dr. Sohee Jeong
ABSTRACT: I would like to present my work on the design and controlled synthesis of solid-state sorbent toward the fundamental understanding of new physical phenomena, with applications in gas storage and capture. My target materials is magnesium borohydride (Mg(BH4)2, abbreviated here MBH) which has recently emerged as a potentially promising material for CO2 capture and hydrogen storage applications due to its naturally porous structure (33% void volume), high theoretical internal surface area (1160 m2/g), high gravimetric hydrogen content (14.9 wt %), and high CO2 uptake (theoretical maximum CO2 uptake of 37.0 mol/kg). However, recent reports for MBH have shown synthetic limitations in terms of yielding desired phase-pure MBH. Consequently, meeting their theoretical physical properties has proven challenging. Here, I demonstrate effective synthetic strategies to obtain pure polymorphic phases of MBH nanomaterials supported by reduced graphene oxide (MBHg) under mild conditions (60 - 190 °C under low vacuum, 2 Torr). Moreover, MBHg nanomaterials exhibit increased CO2 uptake and larger amount of H2 release compared to the parent bulk materials, which was investigated by chemical pathways, microstructural features, as well as structural stability and oxidation resistivity.
BIO: Dr. Sohee Jeong is currently a postdoctoral fellow in Jeffrey Urban’s research group at Lawrence Berkeley National Lab. She earned her Ph.D. in Chemistry at Yonsei University, Korea. Her research interests include the development of new hydrides complex and the rational design of nanomaterials for the energy and environmental applications, with emphasis hydrogen storage and carbon dioxide capture.