【摘要】 本文首先研究了三聚氰胺 (C3N6 H6 )及其低温分解物 (CNxHy,CNx)在高温高压条件下的分解行为 :在压力5 3GPa和温度为 15 0 0K时完全分解为碳 ,同时释放出氨气和氢。我们用元素分析仪 (Perkin -Elmer 2 40CElementalAnalyze)来确定氮和氢的含量。利用三聚氰胺 (C3N6 H6 )及其低温分解物 (CNxHy,CNx)提供氮与氢源 ,研究了氮和氢在粉末触媒合成金刚石中对金刚石生长的影响。我们对合成样品中的黑色物质作了粉末XRD发现 :在高温高压下合成金刚石时 ,碳 -氮化合物 (CNx)与碳 -氮 -氢化合物 (CNxHy)对触媒具有不同的影响作用 ,即 :在合成腔体中大量氮与氢同时存在的条件下 ,Ni70 Mn2 5Co5触媒中的Ni首先与氢发生反应形成氢化物 ,从而改变了金属触媒的原有特性。随着添加不同比例的氮氢化合物的改变 ,分别出现不同的金属氮氢化合物。结果表明 :大量的氮和氢的存在 ,将严重抑制金刚石的成核更多还原

【Abstract】 In this paper, the decomposed behaviors of the melamine （Sam3） and CN_x （Sam1）, CN_xH_y （Sam2） which were prepared from the melamine were investigated under high pressure and high temperature（HTHP）. The CN_x （Sam1）, CN_xH_y （Sam2） and melamine （Sam3） were decomposed into carbon and the NH₃ and active H were given out at 5.3 GPa and 1500K for 15min. The chemical compositions were analyzed by the combustion analysis spectrum for C, N and H on a Perkin-Elmer 240C Elemental Analyzer. The effects of nitrogen and hydrogen, which were from the melamine （C₃N₆H₆）, CN_xH_y, and CN_x decomposed, on diamond synthesized by HPHT were investigated. Powder X-Ray diffraction patterns for the black matter in recovered samples were made respectively. It is found that the influence of CN_x or CN_xH_y or C₃N₆H₆ is different on diamond synthesized with Ni₇₀Mn₂₅Co₅ catalyst by HPHT. That is to say, a great deal of N and H in the synthetic chamber reacted with Ni, Mn and Co in the catalyst, which resulted in the catalyst characteristics changed. The different chemical combination （hydride or nitride） were presented with different proportions of N and H in the CN_xH_y. The results obtained in our study indicate that the nucleation of diamond was destroyed and the graphite/diamond conversion can be completely restrained by the abundant elements N and H in diamond synthesis by （HPHT. ）更多还原