硼砂与氯化铵合成hBN反应机理的研究

REACTION MECHANISM OF Na_2B_4O_7 WITH NH_4Cl IN hBN SYNTHESIS

研究了以硼砂、氯化铵为原料在氨气气氛下合成hBN的反应机理。指出氯化铵在反应中的主要作用是与硼砂反应形成可阻止硼砂颗粒团聚的高熔点膜层 ;而氨气的主要作用就是提供大量参与反应的NH3分子 ,增加了反应几率 ;新生成的hBN则进一步隔离高度熔融的硼砂团粒 ,防止玻璃相的生成。

The reaction mechanism in synthesis of hBN using Na 2B 4O 7 and NH 4Cl as the raw materials in the gas of NH 3 under high-temperature and pressure was studied.The main function of NH 4Cl in the reaction is to form a layer of membrane of high melting-point which can prevent Na 2B 4O 7 particles from assembling.Meanwhile the NH 3 gas provides much active molecules at high temperature to increase reaction ratio in the synthesis of hBN,and the newly formed hBN exists as separator stopping the appearance of glass phase.