摘 要

铯铅溴（CsPbBr3）是一种直接带隙半导体，具有宽禁带宽度（2.25eV），高电阻率（~10¹¹Ω·cm）高平均原子序数（Cs：55，Pb：82和Br：35)，载流子迁移率比较大，寿命也较长，光电导效应突出等优点，满足检测X -ray和γ-ray辐射的大多数需求，同时该晶体具有良好的基本光学性能，金属电极和晶体表面之间具有良好的欧姆接触，满足了光电应用的要求，在发光二极管，太阳能电池，探测器，传感器等方面都有广泛的应用价值。是目前研究的一大热点。

目前，世界上绝大多数的晶体是通过布里奇曼技术制备或从低温溶液中生长获得的。众所周知，布里奇曼生长法中的晶体生长原理是通过将熔融粉末（熔体）从炉子的热区域转移到冷区域的定向凝固。这是通过一个计算机控制的步进电机将安瓿缓慢地转移到炉子较冷的部分来完成的。这种技术所生长的晶体通常会产生缺陷，这是由单晶生长过程中安瓿的机械运动引起的。对于从低温溶液中生长的晶体来说，晶体体积一般较小，晶体中含有大量的由液体包裹体产生的条纹和位错，。因此，人们对钙钛矿单晶的兴趣越来越高，这激发了我们开发简单方法来制备CsPbBr3晶体。

本文运用了固相法并采用了压埋的方式合成CsPbBr3多晶粉末，对钙钛矿化合物CsPbBr3进行了合成、晶体生长、结构检测和光电表征。通过改变反应条件即反应温度、保温时间、成功制备了一批CsPbBr3多晶粉末。同时在CsPbBr3中掺入了硫酸钡，研究了掺硫酸钡对CsPbBr3性能的影响。采用红外光谱、XRD、光学显微镜等测试手段对样品进行表征，研究其结构和性能。

关键词：CsPbBr3晶体 固相法 X射线衍射 荧光检测

Preparation of CsPbBr3 by Solid State Method

Abstract

CsPbBr3 is a direct band gap semiconductor with a wide band gap (2.25 eV) and a high average resistivity (~1011 Ω·cm) atomic average (Cs:55, Pb: 82, and Br: 35). The carrier mobility is relatively large, the lifetime is also longer, and the photoconductive effect is prominent. It satisfies most requirements for the detection of X-ray and gamma-ray radiation. At the same time, the crystal has good basic optical properties, metal electrodes and crystals. The surface has a good ohmic contact, which meets the requirements of photoelectric applications. It has a wide range of applications in light-emitting diodes, solar cells, detectors, sensors and so on. It is a hot topic of current research.

At present, the vast majority of crystals in the world are prepared by the Bridgman technique or grown from a low-temperature solution. It is well known that the crystal growth principle in the Bridgeman growth method is solidification by directional transfer of the molten powder (melt) from the hot zone of the furnace to the cold zone. This is accomplished by a computer-controlled stepper motor that slowly transfers the ampoule to the cooler part of the furnace. Crystals grown by this technique often produce defects, which are caused by the mechanical movement of the ampoule during the growth of the single crystal. For crystals grown from low-temperature solutions, the crystal volume is generally small, and the crystals contain a large amount of fringes and dislocations produced by the liquid inclusions. As a result, there is increasing interest in single crystals of perovskite, which has motivated us to develop a simple method for the preparation of CsPbBr3 crystals.

In this paper, the solid phase method was used to synthesize CsPbBr3 polycrystalline powder. The perovskite compound CsPbBr3 was synthesized, crystal growth, structure detection and photoelectric characterization. A batch of CsPbBr3 polycrystalline powder was successfully prepared by changing the reaction conditions, ie reaction temperature and holding time. At the same time, barium sulfate was doped into CsPbBr3, and the effect of barium sulfate doping on the performance of CsPbBr3 was studied. The samples were characterized by infrared spectroscopy, XRD, and optical microscopy, and their structures and properties were studied.

Key words: CsPbBr3 crystal solid phase method X-ray diffraction fluorescence detection

目录

摘要…………………………………………………………………………………………I

Abstract………………………………………………………………………………II

第一论 1

1.1引言 1

1.2 CsPbBr3的晶体结构 1

1.3 CsPbBr3材料的应用前景 2

1.3.1半导体核辐射探测器 2

1.3.2 绿色发光二极管 2

1.3.3 存储器 3

1.3.4 掺杂ZnO 4

1.3.5 研究目的 5

第二章 样品的制备与表征方法 6

2.1 CsPbBr3晶体的生长 6

2.1.1 CsPbBr3晶体的合成 6

2.2 实验设备 7

2.3 实验原料及试剂 7

2.4 实验步骤 8

第三章 材料的测试与表征技术 11

3.1 X射线衍射分析（XRD） 11

图4.1 a X射线多晶衍射仪构造示意图 11

图4.1 b 衍射仪结构图 11

3.2 荧光光谱仪 13

第四章 总结与展望 16

4.1 总结 16

4.2 展望与不足 16

参考文献 17

致谢 21

第一章 绪论

1.1引言

CsPbBr3的研究开始于20世纪50年代，但是一直没有作为X射线或γ射线探测器材料作为研究。直到近两年才进入室温核辐射半导体体材料的研究领域。

对钙钛矿化合物CsPbBr3进行了合成、晶体生长、结构和光电表征^[1]。这种化合物是一种直接带隙半导体,满足检测X -ray和γ-ray辐射的大多数需求，如高衰减、高电阻率和显著的光电导率响应，具有与市场上最先进材料相媲美的探测器分辨率。在较高温度的晶体生长过程中发生的结构相变似乎不会影响晶体的质量。X -ray和γ-ray探测器在室温下运行是当今科技时代的一个重要方面，由于辐射探测不仅在科学研究方面也在与现代社会福利有关的应用上变得越来越重要，如核医学成像、环境放射性监测和宇宙飞船和国家安全设备等。因为半导体材料的高光谱分辨率和高灵敏度^[2]，所以他们在X -ray和γ-ray辐射探测器方面有极大的潜力。

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