Phase stability limits of Bi₂Sr₂Ca₁Cu ₂O_8+δ and Bi₂Sr₂Ca ₂Cu₃O_10+δ

Abstract

We determined the phase stability limits of Bi2Sr 2Ca1Cu2O8+δ and Bi 2Sr2Ca2Cu3O10+δ in the temperature range 650-880°C using a solid-state electrochemical technique. These phases decompose by incongruent melting above ∼790°C, whereas they decompose by a solid-state reaction at lower temperatures. The solid-state decomposition reaction is reversible for Bi2Sr 2Ca1Cu2O8+δ, but not for Bi2Sr2Ca2Cu3O10+δ.