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Bismuth silicate Bi 4 Si 3 O 12 (BSO) crystal is a fast scintillator which has potential applications in high energy physics, nuclear physics, computed tomography and dosimetry. Compared with widely used Bi 4 Ge 3 O 12 (BGO) crystal, BSO has some better scintillation properties such as a faster decay time, greater radiation hardness and a lower raw material cost, so it is considered to be the substitute for an alternative to BGO crystals. However, two main problems hindered its practical applications: (1) it is difficult to grow large size and high quality crystals due to its compositional segregation; (2) BSO has a relatively low light yield. Recently, large size BSO crystals have been grown by the modified vertical Bridgman method in Shanghai Institute of Technology. The scintillation properties of rare earth doped BSO crystals have been investigated and BSO crystal doped with small amount Dy 2 O 3 increases its light yield remarkably. Furthermore, some experimental results revealed the potential applications of Re-doped BSO crystals in laser and LED fields. In this review, the growth process, scintillation properties and luminescent mechanism of Re or Ge doped BSO crystals were introduced. The spectroscopic properties and energy transfer of Re-doped BSO crystals were discussed based on its applications in laser and LED. As a result, doped BSO crystal is a novel multi-functional material for scintillation, laser and LED applications.

A self-designed traveling zone melting method was employed to fabricate perovskite CsPbBr 3 crystals, which is helpful for impurities removing and moisture excluding. A large-size CsPbBr 3 crystal with a dimension of  25 mm× 60 mm is successfully obtained. The as-grown crystal shows orange color and displays an excellent transmittance of 78.6% in the range of 600 nm  2000 nm wavelength. It is revealed by DSC analysis that there is phase transition at 88.1℃ and 131.25℃, respectively. The band gap E g of the crystal is calculated to be 2.25 eV.The above results prove that the traveling zone melting method is indeed a potential approach for large size and high quality CsPbBr 3 crystal preparation.

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Uranium dioxide is a potential multi-functional material as well as nuclear rod. It exhibits excellent semiconductor performance and anti-irradiation ability. It has the similar band gap (1.3 eV) of silicon crystal (1.1 eV), its Seebeck coefficient is 4 times of the commercial thermoelectric material BiTe, and it shows higher conversion efficiency of solar cells due to its nearly full absorption. These properties make it great potential applications in the fields of semiconductor, solar energy and thermoelectricity. However, the U atoms in uranium dioxide (UO 2±x ) can vary from -0.5 to 1, which is called hyperstoichiometric characteristics, resulting in some problems in crystal growth and property homogeneity. In this paper, we analyzed the structure and chemical stability of uranium oxides according to U-O phase diagrams, summarized recent research progress on crystal growth and physical properties of UO 2 crystals. UO 2 is an ideal Mott insulator with a stable electric conductivity, while the hyperstoichiometric UO 2±x crystals are semiconductors, and their physical properties, including electric conductivity, thermal conductivity and diffusion coefficient, and optical properties, are closely related to x. So far, UO 2 crystals have grown via several methods, such as chemical vapor transport (CVT), sublimation, skull melting, hydrothermal and flux. The skull melting and hydrothermal techniques are expected to improve crystal dimensions and quality in future. The growth of UO 2 crystals is ex-