High pressure electrical transport behavior in SrF2 nanoplates**Project supported by the National Natural Science Foundation of China (Grant Nos. 11374131, 11674404, 11404137, and 61378085), the Program for New Century Excellent Talents in University, China (Grant No. NCET-13-0824), the Program for the Development of Science and Technology of Jilin Province, China (Grant Nos. 201201079 and 20150204085GX), and the Twentieth Five-Year Program

Abstract

The charge transport behavior of strontium fluoride nanocrystals has been investigated by in situ impedance measurement up to 35 GPa. It was found that the parameters changed discontinuously at each phase transition. The charge carriers in SrF2 nanocrystals include both F ions and electrons. In the phase, pressure makes the electronic transport easier, while makes it more difficult in the Pnma phase. The defects at grain boundaries dominate the electronic transport process. Pressure could make the charge–discharge processes in the phase much easier, but make it more difficult in the Pnma phase.