2023年11月20日 · At 1000 °C, the XRD spectrum shows the phase of HfO 2 as the precursor powders transformed into crystalline HfO 2. At 1100 °C, HfO 2 is still the dominant product, but the typical XRD peaks of HfB 2 can be seen by magnification (Fig. …

2022年12月30日 · Generally, the HfB 2 powder prepared without dispersant demonstrates an XRD pattern well-matched with the standard XRD patterns of HfB 2 (JCPDS card, no. 65–3389). Similar XRD patterns can be also observed on the samples prepared using PEG and PVP, suggesting their high purity.

2013年7月1日 · Relative density was calculated by dividing measured density by theoretical density calculated using the rule of mixtures. Geometrical methods were also used to confirm the validity of measured densities. The phase composition was analyzed with X-ray diffraction (XRD) in a Philips PW7100 diffractometer using Cu-K α radiation. All compositions ...

HfB2 is hexagonal omega structure structured and crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Hf is bonded to twelve equivalent B atoms to form a mixture of edge and face-sharing HfB12 cuboctahedra.

The XRD spectra of the CVD consolidated HfC coatings are presented in Figure 5. All coatings had just HfC diffraction peaks visible, which supports the production of pristine HfC coatings. Crystallization of HfC phases is manifested as sharp and narrower diffraction peaks. Strong (200) peak and a number of lesser peaks are displayed in Figure 5 ...

Download scientific diagram | XRD pattern (a) and molecular model diagram (b) for HfB2 from publication: A novel hafnium boride catalyst for vanadium redox flow battery | Vanadium redox flow ...

2021年5月10日 · HfB 2, Si, and activated carbon powders were selected to fabricate 0–30 vol% SiC reinforced HfB 2 -based composite. Pressureless sintering process was performed at 2050 °C for 4 h under a...

We present a detailed magnetotransport study on HfB₂, a possible topological nodal-line semimetal. HfB₂ exhibits field-induced resistivity upturn and plateau behaviors at low...

X 射线粉末衍射 (XRD) 图案可以索引为六方 HfB2，晶格常数为 a=3.146 和 c=3.456 A。 透射电子显微镜 (TEM) 图像显示平均尺寸为 25 nm 的颗粒形态。 选区电子衍射 (SAED) 图案证实了六方 HfB2 的存在。

2024年7月10日 · 为了提高高熵硼化物陶瓷的性能，扩大高熵硼化物陶瓷家族，本文在铪基三元硼化物中引入WB2，通过硼热/碳热还原法与SPS结合制备（Hf0.25Zr0.25W0.25Ti0.25）B2新型四元高熵硼化物陶瓷，研究其物相组成、显微结构和力学性能。