Hole Doping and Oxygen-Pressure Stability Studies in the Layered Cuprate Ca0.85Sr0.15CUO2

✍ Scribed by P. Strobel; J. Decker; C. Prouteau; R. Argoud

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 223 KB
• Volume: 112
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.1994.1328

✦ Synopsis

The possibility of hole doping in (\mathrm{Ca}{0.85} \mathrm{Sr}{0.15} \mathrm{CuO}{2}) was studied by either partial substitution of alkaline-earth cations by (\mathrm{Li}) and (\mathrm{Na}) or by annealing in oxygen pressures up to (200 \mathrm{~atm}). Li substitution does not modify significantly the cell parameters, but results in changes in (\mathrm{X})-ray reflection intensities and increases in electrical conductivity. Sodium does not substitute in the (\mathrm{Ca}{0.85} \mathrm{Sr}{0.15} \mathrm{CuO}{2}) phase. Oxygen-pressure treatments up to (975^{\circ} \mathrm{C}) and (200 \mathrm{~atm} \mathrm{O}{2}) show a reversible trausformation between layered (\mathrm{Ca}{4 ., .5 .5} \mathrm{Sr}{(0.15} \mathrm{CuO}{2}) and the chain-containing (\mathrm{Ca}{6} \mathrm{Cu}{7} \mathrm{O}_{14}), which is more stable at high oxygen pressure. if 1994 Acatemtc Press, fne.