Available on-demand - S.EN11.04.13
Hydrogen Boride Sheets—Synthesis, Characterization and Application
Takahiro Kondo1
University of Tsukuba1
Show Abstract
Two-dimensional (2D) materials consisting of a single or a few layers of atoms have superior performance compared to conventional materials or their bulk counterparts in a variety of applications, because of their unique properties, including their flexibility, high specific surface area, and quasi-2D electron confinement. Recently, we have revealed that the hydrogen boride (HB or borophane) sheets with an empirical formula of H1B1 can be formed by exfoliation and complete ion-exchange between protons and magnesium cations in magnesium diboride (MgB2) with an average yield of 42.3% at room temperature [1], as a new member of 2D sheets and boron-based nanomaterials [2]. The sheets feature an sp2-bonded boron planar structure without any long range order. A hexagonal boron network with bridge hydrogens is suggested as the possible local structure, where the absence of long range order was ascribed to the presence of three different anisotropic domains originating from the 2-fold symmetry of the hydrogen positions against the 6-fold symmetry of the boron networks. Our recent analysis with soft x-ray absorption and emission spectroscopy at the B K-shell also supports this view and show the semimetallicity of HB sheets [3]. We have then found several intriguing properties of HB sheets for the applications of hydrogen (H2) release (as muh as 8 wt%) by UV irradiation at room temperature under mild ambient conditions [4], and the solid-acid catalyst [5] that convert C2H5OH to C2H4 and water. In the presentation, synthesis, characterization, and application of HB sheets will be introduced.
Acknowledgement
This work was done with Mr. H. Nishino, Prof. T. Fujita, Dr. N. T. Cuong, Dr. S. Tominaka, Prof. M. Miyauchi, Prof. S. Iimura, Dr. A. Hirata, Dr. N. Umezawa, Prof. S. Okada, Prof. E. Nishibori, Mr. A. Fujino, Mr. R. Ishibiki, Mr. T. Goto, Dr. S. Ito, Dr. Tateishi, Prof. Niibe, Prof. J. N. Kondo, Dr. T. Fujitani, Prof. I. Matsuda, Prof. J. Nakamura, and Prof. H. Hosono.
[1] H. Nishino, T. Fujita, N. T. Cuong, S. Tominaka, T. Kondo*, et al., J. Am. Chem. Soc. 139, 13761 (2017).
[2] T. Kondo*, Sci. Technol. Adv. Mater. 18, 780 (2017).
[3] I. Tateishi, N. T. Cuong, C. A. S. Moura, T. Kondo, et al. Phys. Rev. Mate. 3, 024004 (2019).
[4] R. Kawamura, N. Cuong, T. Fujita, T. Kondo*, M. Miyauchi*, et al., Nature Communications, 410, 4880 (2019).
[5] A. Fujino, S. Ito, T. Goto, R. Ishibiki, T. Kondo*, et al., ACS Omega, 4, 14100 (2019).