Results for “HfCl4” | Engineering Papers

DOE OSTI2020

Materials Data on HfCl4 by Materials Project

HfCl4 crystallizes in the monoclinic P2/c space group. The structure is one-dimensional and consists of one HfCl4 ribbon oriented in the (1, 0, 0) direction. Hf4+ is bonded to six Cl1- atoms to form edge-sharing HfCl6 octahedra. There are a spread of Hf–Cl bond distances ranging from 2.32–2.66 Å. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a water-like geometry to two equivalent Hf4+ atoms. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Hf4+ atom.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Synthesis and Flash Sintering of (Hf1-xZrx)B2 Solid Solution Fine Powders

Fine powders of (Hf1-xZrx)B2 solid solution were synthesized by two methods. In the first one, solution-based processing of HfCl4, ZrCl4, sucrose and H3BO3 was carried out followed by heat treatment (e.g., at 1500 °C for 1 h) in Argon to achieve the carbothermal reduction (CTR) reaction to form the boride solid solution. In the second one, called boron hydride reduction (BHR) method, HfCl4, ZrCl4 and NaBH4 were directly mixed in a glove box followed by heat treatment in Argon at elevated temperatures from 700 to 1500 °C. In addition, the powders synthesized via both methods were flash sintered without sample preheating in a homemade setup. The synthesized powders as well as the flash sintered bulk ceramics were characterized using different techniques including XRD, SEM, EDS, TEM, TGA-DSC, and Vickers hardness test to reveal the inter-relationships between starting materials composition, processing conditions, and the resulting materials microstructure and physical/chemical properties.

Belisario, Jose↗