钇钡铜氧超导膜溶液法沉积过程中氟化钡中间相的热力学分析 Thermodynamics Analysis on BaF2 Intermediate Phase in Solution-Derived YBCO Superconducting Film Deposition

在使用化学溶液沉积技术制备钇钡铜氧高温超导薄膜的过程中，氟化钡是一种重要的热处理中间相。在本文中，通过对氟化钡向其他中间相转化的化学反应进行标准吉布斯自由能变计算，对氟化钡的热力学稳定性进行了分析，考虑的温度范围为700至1000开尔文。计算中使用了物质吉布斯自由能函数法和物质生成标准摩尔吉布斯自由能法两种方法，计算标准吉布斯自由能变。该研究验证了氟化钡在较高温度下相对于其他中间相的生成优先性，同时也发现了700开尔文下碳酸钡相生成的可能性。 In the YBa2Cu3O7-δ (YBCO) high temperature superconducting thin film fabrication via the chemical solution deposition method, BaF2 is an important intermediate phase during heat treatment. In this paper, BaF2 thermodynamics stability was analyzed through calculating the standard Gibbs free energy change (ΔGT) of the reactions related to other intermediate phases within the temperature range of 700 - 1000 K. Two thermodynamics methods, the Gibbs free energy function method and standard formation molar Gibbs free energy method, were utilized to obtain the ΔGT values. This study confirms the formation priority of BaF2 relative to other mesophase at high temperatures while the possibility of BaCO3 formation was found at 700 K.