title: In Situ NMR Study on the Interaction between LiBH4-Ca(BH4)2 and Mesoporous Scaffolds.
abstract: We discuss the use of nuclear magnetic resonance (NMR) spectroscopy to investigate the physical state of the eutectic composition of LiBH4-Ca(BH4)2 (LC) infiltrated into mesoporous scaffolds and the interface effect of various scaffolds. Eutectic melting and the melt infiltration of mixed borohydrides were observed through in situ NMR. In situ and ex situ NMR results for LC mixed with mesoporous scaffolds indicate that LiBH4 and Ca(BH4)2 exist as an amorphous mixture inside of the pores after infiltration. Surprisingly, the confinement of the eutectic LC mixture within the mesopores is initiated below the melting temperature, which indicates a certain interaction between the borohydrides and the mesoporous scaffolds. The confined borohydrides remain inside of the pores after cooling. These phenomena were not observed in microporous or nonporous materials, and this observation highlights the importance of the pore structure of the scaffolds. Such surface interactions may be associated with a faster dehydrogenation of the nanoconfined borohydrides.
authors: †High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea.
authors: Hyun-Sook
authors: HS
authors: Lee
authors: ‡Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
authors: Son-Jong
authors: SJ
authors: Hwang
authors: ‡Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
authors: Hoon Kee
authors: HK
authors: Kim
authors: †High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea.
authors: Young-Su
authors: YS
authors: Lee
authors: §Department of Advanced Materials Chemistry, WCU Research Center, Korea University, 208 Seochang, Jochiwon, Chungnam 339-700, Republic of Korea.
authors: Jinsol
authors: J
authors: Park
authors: §Department of Advanced Materials Chemistry, WCU Research Center, Korea University, 208 Seochang, Jochiwon, Chungnam 339-700, Republic of Korea.
authors: Jong-Sung
authors: JS
authors: Yu
authors: †High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul 136-791, Republic of Korea.
authors: Young Whan
authors: YW
authors: Cho
keywords: borohydride; hydrogen storage; in situ NMR; nanoconfinement; porous carbon