la 2 O 3 + 15b→2lab 6 + 3bo↑(S1)将少量的硼(3 wt%)引入初始电荷中,以补偿由于合成温度下蒸气的高压而导致的硼可能损失。将电荷机械混合几天,至少在筛子中筛分至少5次,以便基于氧化物和硼打破砾岩,并尽可能地制备均匀的混合物。将准备好的混合物压入片剂中,直径为15毫米,高度为10毫米,在1650 0 C的温度下将其保持在真空炉中一个小时C,以约30度/分钟的速度缓慢升高,以确保去除所得气体。The equation (S1) reflects the overall reaction (initial (left side) and final (right side) stages), but the reduction reaction itself goes through intermediate stages that include the formation of borate (LaBO 3 ), a trace amount of hexaboride (LaB 6 ) and free boron (B free ) (~1055 0 C) and the subsequent reaction of the LaBO 3 with the remaining boron to form a hexa boride (1175 0 c)[1]