In order to control the size and the shape of crystals, we have investigated different experimental growth parameters such as temperature and precursor concentration. The morphology of obtained crystals was observed by optical microscope, whereas their intrinsic crystalline properties were characterized by single crystal as well as powder X-ray diffraction. The results illustrated that the growth and crystalline structure of mixed halide perovskites CH3NH3PbI3−xBrx could be easily tuned. | Communications in Physics, Vol. 28, No. 3 (2018), pp. 237-245 DOI: GROWTH OF SINGLE CRYSTALS OF METHYLAMMONIUM LEAD MIXEDHALIDE PEROVSKITES THUAT NGUYEN-TRANa,† , NGOC MAI ANa , THU TRANG LUONGb , HUNG HUY NGUYENb AND THANH TU TRUONGb a Nano and Energy Center, VNU University of Science, 334 Nguyen Trai, Thanh Xuan District, Hanoi, Vietnam b Faculty of Chemistry, VNU University of Science, 19 Le Thanh Tong, Hoan Kiem District, Hanoi, Vietnam † E-mail: thuatnt@ Received 11 June 2018 Accepted for publication 23 July 2018 Published 31 August 2018 Abstract. We report the growth and characterization of different bulk single crystals of organo lead mixed halide perovskites CH3 NH3 PbI3−x Brx by two different crystal growth approaches: (i) anti-solvent diffusion, and (ii) inverse temperature crystallization. In order to control the size and the shape of crystals, we have investigated different experimental growth parameters such as temperature and precursor concentration. The morphology of obtained crystals was observed by optical microscope, whereas their intrinsic crystalline properties were characterized by single crystal as well as powder X-ray diffraction. The results illustrated that the growth and crystalline structure of mixed halide perovskites CH3 NH3 PbI3−x Brx could be easily tuned. Keywords: Organo lead mixed halide perovskites, single crystal, CH3 NH3 PbI3−x Brx . Classification numbers: ; . c 2018 Vietnam Academy of Science and Technology 238 THUAT NGUYEN-TRAN et al. I. INTRODUCTION Until now, the power conversion efficiency of hybrid organo metal halide perovskite solar cells has significantly increased up to [1]. These up-to-the-minute new devices surpassed other third-generation solar cells to become the most promising rival to the silicon-based solar cells due to their superiorities, such as high charge carrier motilities, low temperature (below 150˚C) solution process, extreme large
