Zr掺杂对碳化硼晶格结构的影响

STRUCTURAL CHANGES OF BORON CARBIDE INDUCED BY Zr INTRODUCTION

采用热压制备方法就掺杂0．5％Zr(原子分数）对B4.3C晶格结构的影响进行了研究．XRD分析表明，样品中形成了B4.3C，（BN）4H以及（ZrB2）3H相．掺Zr的确改变了B4.3C的结构，尤其是在C-B-C链中间的B（3）处出现了明显的空位Zr掺杂元素的影响看来是很特别的，因为用Ni做了相同的掺杂后并没有发现类似的结构改变.XPS研究表明,Zr掺杂原子处于不饱和键状态．分析结果表明Zr进入了B4.

Zr doped boron carbide (B4.3C) semiconductor was prepared by hot pressing of mixture of boron carbide powder (B4.3C) and Zr nanocrystals (0.5%, atomic fraction), to investigate influence of impurity incorporation on the subtle structure of B4C crystals. XRD analyses indicated that the hot-pressed sample was composed of B4.3C, (BN)4H, and (ZrB2)3H. Zr introduction does have modified the B4.3C structure. Especially, remarkable vacancies were led into on the B(3) sites of the C-B-C chain centre.The effect of Zr incorporation seems to be unique because similar structural change was not observed by the same experimental procedure with Ni doping. XPS studies revealed that the Zr atoms existed in a state with unsaturated bonding. B4.3C with interstitial Zr atoms is speculated.