A computational study of energy barriers of structural transformations and hydrogen transfer in boehmite. Issue 5 (9th January 2018)

• Record Type: Journal Article
• Authors: Jiang, Yingjian; Xie, Yaoping; Guo, Haibo
• Is Part Of: RSC advances. Volume 8:Issue 5(2018)
• Page Start: 2377
• Page End: 2384
• Publication Date: 2018-01-09
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7ra12273j
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Energy barriers for hydrogen-transfer processes are generally below 21 kJ mol −1 in a perfect crystal, and 14 kJ mol −1 in a vacancy-containing structure. The low energy barriers are indicators of the high proton conductivity of boehmite. Abstract : The crystal structure of boehmite (γ-AlOOH) contains a large amount of hydrogen bonds that are joined into chains by sharing hydrogen-bond donor and acceptor oxygen atoms. The hydrogen ions in the hydrogen-bond chains are highly mobile and have complicated structural characterizations, and this feature may well be utilized for proton-conducting applications, but the mechanism is unknown without the dynamic parameters of the hydrogen-transfer processes. We propose probable hydrogen-transfer paths and compute their energy barriers using density functional theory with van der Waals density functionals, on both perfect and vacancy-containing crystal structures. It is revealed that the energy barriers are generally below 21 kJ mol −1 in a perfect crystal, and 14 kJ mol −1 in a vacancy-containing structure. The low energy barriers are indicators of the high proton conductivity of boehmite even at room temperature.