【摘要】 采用水热重结晶法提纯TlBr,用等离子耦合质谱仪检测痕量杂质。结果表明:水热重结晶法是一种有效的TlBr提纯方法,经一次水热重结晶提纯后,杂质Ca,Fe,Mg,K,Zn,Cu,Na和Si的总浓度从139.6×10–6(质量分数,下同)下降为9.3×10–6;随着溶液冷却速率的下降,杂质含量下降幅度明显增大。对比真空蒸馏提纯法,水热重结晶法具有更高的提纯效率。以水热重结晶制备的TlBr粉为原料,采用垂直Bridgman法生长了尺寸为φ8mm×55mm的TlBr晶体。TlBr晶体的禁带能为(2.83±0.005)eV,电阻率为2.26×1011(Ω·cm)。更多还原

【Abstract】 TlBr powder was purified by the hydrothermal re-crystallization (HRC) method. Trace elements were analyzed using inductively coupled plasma mass spectrometry. The sum concentration of impurities of Ca, Fe, Mg, K, Zn, Cu, Na, and Si in the powder can be dropped from 139.6 × 10–6 (mass fraction, the same below) to 9.3 × 10–6 after one run of HRC. The purification efficiency of HRC shows that it is an effective method for the removal of impurities from TlBr powder. The impurity concentration decreases evidently with the reducing of the cooling rate in the HRC process. In contrast with vacuum distillation method, the HRC method has much high purification efficiency. The bandgap value of the TlBr crystal with 8 mm in diameter and 55 mm long grown by the vertical Bridgman method using the HRC powder as raw material is (2.83 ± 0.005) eV, and its resistivity value is 2.26 × 1011 (Ω·cm).更多还原