Phase segregation in Mn-doped In2O3: in situ high-pressure high-temperature synchrotron studies in multi-anvil assemblies

Abstract

The goal of the present work is to study the effect of doping on the pressure-induced phase transitions in In 2 O 3 . Manganesedoping was chosen for the present study because the stable ambient pressure phases of the pure oxides (hereafter denoted as c-In 2 O 3 and c-Mn 2 O 3 ) both have bixbyite-type (space group Ia-3, No. 206) structure but are crystallized in different structures at higher pressures and temperatures, as displayed in Fig. 1 In previous investigations laser-heated diamond-anvil cells (DACs) were employed to compress and heat c-In 2 O 3 specimens.6-7,10-12 However, temperatures below 1000 uC, where several phase transitions in In 2 O 3 are expected, are very difficult to control with this technique. Externally heated DACs may be used, but would also produce very limited amounts of a high-pressure polymorph that can be recovered to ambient conditions. A synthesis method providing both in situ control and macroscopic quantities of the target material, suitable for physico-chemical characterization after quenching from high pressure and temperature is available in the form of large volume (multi-anvil) presses at synchrotron facilities. 13 For the present study, the phase development in Mn-doped c-In 2 O 3 was followed in situ by energydispersive X-ray diffractometry at the two stage 6-8 MAX200X multi-anvil high pressure diffractometer of the GFZ Potsdam (beamline W2, HASYLAB/DESY, Hamburg, Germany). New high-pressure/high-temperature multi-anvil assemblies for synchrotron studies developed at the Freiberg High Pressure

Orthorhombic In2O3: A Metastable Polymorph of Indium Sesquioxide

“…New high‐pressure/high‐temperature multi‐anvil assemblies for synchrotron studies developed at the Freiberg High Pressure Research Centre are employed 18. These assemblies have low X‐ray absorption and do not show any additional reflections from the sample environment (see the Supporting Information) 19…”

Orthorhombisches In2O3 – ein metastabiles Indiumsesquioxid‐ Polymorph

“…Dabei kommen Hochdruck‐Hochtemperatur‐Mehrstempelzellenanordnungen zum Einsatz, welche am Freiberger Hochdruck‐Forschungszentrum neu entwickelt wurden 18. Diese haben eine geringere Röntgenabsorption und zeigen keine zusätzlichen Reflexe der Probenumgebung (siehe die Hintergrundinformationen) 19…”