Solution Growth of High-Quality (C<sub>8</sub>H<sub>20</sub>N)<sub>2</sub>Cu<sub>2</sub>Br<sub>4</sub> Single Crystal Scintillators

有机–无机杂化钙钛矿材料凭借其出色的发光性能以及可调的材料性质，在辐射探测领域中成为一项关键的研究方向。然而，如何制备高质量、低缺陷的钙钛矿单晶，仍然是当前技术面临的重大挑战。本文采用优化的籽晶降温法，成功制备出尺寸为20 × 6 mm的大尺寸(C8H20N)2Cu2Br4单晶。此方法通过精确控制溶液的温度和浓度变化，避免了溶液成分剧烈波动导致的杂质生成，并显著提高了晶体的尺寸与质量。结合对晶体结构的解析和材料的表征，证明该晶体具有高纯度和优异的化学稳定性，且晶体结构与理论预测高度一致。发光性能测试显示该晶体在室温下展现出475 nm的蓝光发射，光致发光量子产率高达99.3%，并具有显著的146 nm的大斯托克斯位移。综上所述，本文提出的制备方法为钙钛矿单晶闪烁体的高质量生长提供了新的思路，并为其在辐射探测领域的进一步应用奠定了基础。Organic-inorganic hybrid perovskite materials have become a key research direction in the field of radiation detection due to their excellent luminescent properties and tunable material characteristics. However, the fabrication of high-quality, low-defect perovskite single crystals remains a significant challenge in current technologies. In this study, a modified seed crystal cooling method was used to successfully prepare large-sized (C8H20N)2Cu2Br4 single crystals with dimensions of 20 × 6 mm. This method avoids the generation of impurities caused by drastic fluctuations in solution composition by precisely controlling the temperature and concentration changes in the solution, which significantly enhances the size and quality of the crystals. Structural analysis and material characterization confirm that the crystal has high purity and excellent chemical stability, with the crystal structure aligning well with theoretical predictions. Photoluminescence tests show that the crystal emits blue light at 475 nm at room temperature, with a photoluminescence quantum yield as high as 99.3%, and exhibits a significant 146 nm Stokes shift. In conclusion, the preparation method proposed in this paper provides a new approach for the high-quality growth of perovskite single crystals and lays the foundation for further applications in the field of radiation detection.