41927-88-2Relevant articles and documents
Static observation of the interphase between NaBH4 and LiI during the conversion reaction
Hihara, Takehiko,Miyagawa, Reina,Miyazaki, Reona,Onishi, Keita
, (2021/08/10)
To determine the synthesis conditions for NaI–NaBH4–LiI solid solutions in a single phase, the conversion reaction of NaBH4 ?+ ?LiI → NaI ?+ ?LiBH4 was investigated by preparing mixed pellets of NaBH4/LiI. The extent of the reaction was investigated under different reaction temperatures and pressures. Although it was not possible to completely suppress the conversion reaction in this study, the low temperature and high-pressure conditions were shown to be favorable to avoid the presence of LiBH4. A significant point is that the conversion reaction was investigated in a static condition in the form of pellets, whereas most of the metal borohydride-halide composites have been fabricated by ball-milling. The microstructure of NaBH4/LiI mixed pellets at different ageing times was observed by scanning electron microscope (SEM), Auger electron spectroscopy (AES), wavelength dispersive X-ray spectroscopy (WDS) and time of flight secondary ion mass spectroscopy (ToF-SIMS). The analysis revealed that the reaction interphase between NaBH4 and LiI occurs in the order of LiI/NaI/LiBH4/NaBH4. It was clearly confirmed that the growth of the NaI layer continued with time even at room temperature. In conjunction with the array of the interphase, the diffusion of Na+ in LiBH4 appears to be a necessary condition for the growth of the NaI layer. The present results suggest that a detailed investigation of the conversion reaction between other metal borohydrides and halides (for example, CeCl3/LiBH4, ZrCl4/KBH4, etc.) in the static condition would likely reveal the diffusion of the new ions in the existing compounds.
Ion Exchange of Layered Alkali Titanates (Na2Ti3O7, K2Ti4O9, and Cs2Ti5O11) with Alkali Halides by the Solid-State Reactions at Room Temperature
Ogawa, Makoto,Saothayanun, Taya Ko,Sirinakorn, Thipwipa Tip
, p. 4024 - 4029 (2020/04/08)
Ion exchange of layered alkali titanates (Na2Ti3O7, K2Ti4O9, and Cs2Ti5O11) with several alkali metal halides surprisingly proceeded in the solid-state at room temperature. The reaction was governed by thermodynamic parameters and was completed within a shorter time when the titanates with a smaller particle size were employed. On the other hand, the required time for the ion exchange was shorter in the cases of Cs2Ti5O11 than those of K2Ti4O9 irrespective of the particle size of the titanates, suggesting faster diffusion of the interlayer cation in the titanate with lower layer charge density.
Origin of the thermal desorption peaks of gases in NaI above 180°C
Sofronov,Kudin,Voloshko, A. Yu.,Kudin,Shishkin
, p. 1314 - 1318 (2010/03/25)
We analyze the origin of the water desorption peaks in NaI above the temperature stability range of the crystalline hydrate NaI ? 2H 2O. The two water desorption peaks at t ≥ 180°C are shown to arise from the decomposition of aqua complexes bas