Prof. Bertil Sundqvist [Umeå University, Sweden]
Title: Li+ ions on the move: two Li compounds studied under pressure | 锂离子的运动：压力下两个锂化合物的研究
Time: 10:00 - 11:00 AM, Thursday, November 3, 2016
Place: Conference room 410, HPSTAR (Shanghai)
Host: Dr. Lin Wang
Li+ ions easily move in many solid and liquid media. This is the basis for the lithium batteries now used in applications from watches and smartphones to large vehicles. Although Li+ ion transport has been studied very extensively in many materials, rather few studies have been made under pressure. Here, the results of two recent experimental studies will be presented. The transport properties have been studied up to 2 GPa in two solid materials, LiBH4, also considered for applications in hydrogen storage, and Li4C60, a carbon-based material recently reported to be a superionic conductor. Although we expect that the ionic conductivity should decrease when the lattice is compressed, neither material shows a strong tendency in that direction. For LiBH4 we find possible evidence for a previously unknown phase transformation at low pressure, while for Li4C60 we show that electronic conduction may, in fact, dominate at all pressures, including atmospheric.
Biography of the Speaker:
Carried out research in Condensed Matter Physics/Materials Science since 1972 leading to 299 refereed publications (see appendix) and more than 3100 citations in the Web of Science Science Citation Index (Hirsch factor 26). Research areas have, very briefly described, been
- thermal conductivity and resistivity of metals and alloys under pressure,
- superconductivity in metals, alloys, and ceramic high-Tc materials,
- transport and structural properties of graphite and graphite intercalation compounds,
- properties of conducting polymers, both intrinsic and composite, under pressure,
- the structural, pVT, vibrational and transport properties of nanostructured carbon, i.e. fullerenes, “doped” fullerenes, and empty, filled and doped carbon nanotubes, and
- the phase diagrams of light metal hydrides and borohydrides under pressure.
I have also developed experimental methods and high pressure devices, and designed and invented electronic circuits.
Most of these projects have been carried out in international collaboration, and over the last few years I have co-authored papers with colleagues from at least ten countries.