β Scribed by Takayuki Terai; Yoichi Takahashi
No coin nor oath required. For personal study only.
The sorption behaviors of hydrogen gas at 77K on several different potassium-carbon intercalation compounds (KC,) have been studied. Samples of KC, were prepared from petroleum-coke carbons heat-treated at 800, 1000, 1500 and 2300Β°C by the modified two-bulb method. The isotherms of hydrogen absorption and the isotropic H,-HT partition coefficients between the absorbed phase and the gas phase determined on them were found to be considerably influenced by the composition of KC, as well as the heat-treatment temperature (HTT) of the starting carbon materials. In order to account for such behavior, which is not only different from those of ordinary compounds prepared from graphite but inconsistent with the so-called KC-KC,, mixture model, a possibility is suggested that there may exist an absorptive intermediate phase between KC, and KC,, in the case of KC, compounds prepared from low-HTT-carbons.
π SIMILAR VOLUMES
The fluorination of highly oriented pyrolytic graphite (HOPG), powdery and flaky natural graphites, and carbon fiber (P 100) has been performed in a fluorine atmosphere with HF gas (5.3 x 103-4.8 x lo4 Pa), or by flowing fluorine gas in anhydrous liquid hydrogen fluoride (AHF) at ambient temperature