High-Pressure and High-Temperature Synthesis and In Situ High-Pressure Synchrotron X-ray Diffraction Study of HfSi2.
High-Pressure and High-Temperature Synthesis and In Situ High-Pressure Synchrotron X-ray Diffraction Study of HfSi2.
复制标题
DOI：
10.1021/acs.inorgchem.1c01681
复制
发表时间：
2021-10
影响因子：
4.6
通讯作者：
Weiwei Li;Pei Wang;Chao Xu;Hu Tang;Pengyuan Ren;Zhiqing Xie;Xuefeng Zhou;Jian Chen;Shanmin Wang;Songbai Han;Yusheng Zhao;Liping Wang
中科院分区：
文献类型：
--
作者：
Weiwei Li;Pei Wang;Chao Xu;Hu Tang;Pengyuan Ren;Zhiqing Xie;Xuefeng Zhou;Jian Chen;Shanmin Wang;Songbai Han;Yusheng Zhao;Liping Wang
在DS6 × 10 MN六面顶压机上，采用高压高温（HPHT）法在3GPa、1573 K下成功合成了高质量的HfSi 2。适度的合成温度是由显着降低液相线和固相线温度在高压下的Hf-Si二元系的富Si部分的帮助。原位高压X射线衍射研究得到HfSi_2的体积模量为B_0 = 124.4 ± 0.8 GPa，固定B_0 ' = 4.0，表现出显著的各向异性压缩性，a轴和c轴的不可压缩性几乎是B轴的两倍。合成的HfSi 2块体具有6.9 ± 0.1 GPa的维氏硬度和1163 K的高热稳定性，表明其具有坚硬和耐火的陶瓷性能。在HfSi_2、HfSi、Hf和Si粉的体样品上收集了Hf_4f和Si_2 p的芯层XPS数据，以研究铪硅化物中的Hf-Si键合。Hf 4f 7/2结合能分别为15.0和14.8 eV的体HfSi 2和HfSi。
High-quality hafnium disilicide (HfSi2) has been successfully synthesized using a high-pressure and high-temperature (HPHT) method at 3 GPa and 1573 K in a DS6 × 10 MN cubic press. The modest synthesis temperature is aided by significant decreases in both liquidus and solidus temperatures at high pressure for the Si-rich portion of the Hf-Si binary system. The in situ high-pressure X-ray diffraction study yielded a bulk modulus of B0 = 124.4 ± 0.8 GPa with a fixed B0' = 4.0 for HfSi2, which exhibits a dramatically anisotropic compressibility, with a and c axes nearly twice as incompressible as the b axis. The bulk HfSi2 as synthesized has a Vickers hardness of 6.9 ± 0.1 GPa and high thermal stability of 1163 K in air, indicating its hard and refractory ceramic properties. The core-level XPS data of Hf 4f and Si 2p have been collected on the bulk samples of HfSi2, HfSi, and Hf, as well as Si powder to examine the Hf-Si bonding in hafnium silicides. The Hf 4f7/2 binding energies are 15.0 and 14.8 eV for bulk HfSi2 and HfSi, respectively.