Effect of the size of CuBr nanocrystals formed in potassium-aluminum-borate glass on the phase transformation temperature

Abstract

At thermal treatment of samples of potassium aluminum borate glass containing Cu and Br, a heterogeneous nanophase is formed as drops of the liquid containing CuBr and KBr. At room temperature, the phase contains CuBr and K 2 CuBr 3 nanocrystals. The effect of sizes of nanophase areas on the tempera tures of phase transformations (liquidus, solidus, and crystallization) at heating and cooling has been inves tigated. At the sizes of CuBr crystals equal to 10 nm, the solidus temperature is close to that shown on the state diagram of the KBr-CuBr system. The decrease of the sizes of CuBr crystals from 10 to 4.5 nm results in the decrease of the solidus temperature from 170 to 95°C and the liquidus temperature from 208 to 120°C: in other words, the dimensional effect is manifested almost identically on the values of the solidus and liqui dus temperatures. The decrease of the sizes of the liquid drops from 19 to 7 nm results in the decrease of the crystallization temperature from 100 to 70°C.

In situ precipitation of Cs3Cu2I5 nanocrystals in inorganic glass with long-term water stability for X-ray imaging

“…I-VII, II-VI, IV-VI and perovskite quantum dots have been successfully precipitated in different glass matrices. [19][20][21][22][23][24][25] In addition, Cs 3 Cu 2 I 5 NCs exhibit optical properties comparable to those of other bulk materials such as Cs 3 Cu 2 I 5 powders, Cs 3 Cu 2 I 5 films, and so on. [26][27][28] Inspired by these works, we try to precipitate Cs 3 Cu 2 I 5 NCs in glass.…”