论文标题
设计高度有序的无铅双钙钛矿卤化物设计
Highly ordered lead-free double perovskite halides by design
论文作者
论文摘要
无铅双钙钛矿卤化物是新兴的光电材料，是铅基钙钛矿卤化物的替代品。最近，合成了单晶双钙钛矿卤化物，并证明了它们有趣的功能性能。尽管有这样的开创性作品，但具有更好结晶度的无铅双钙钛矿卤化物仍需应用于新型的光电设备。在这里，我们意识到高度结晶的CS2Agbibr6单晶具有微观尺度上定义明确的原子序。我们通过操纵水热合成中的初始化学环境来避免AG空位的形成和随后的次级CS3BI2BR9。 AG空缺的抑制使我们能够降低生长晶体中的陷阱密度，并进一步增强载体迁移率。我们的设计策略适用于制造具有高结晶度的其他无铅卤化物材料。
Lead-free double perovskite halides are emerging optoelectronic materials that are alternatives to lead-based perovskite halides. Recently, single-crystalline double perovskite halides were synthesized, and their intriguing functional properties were demonstrated. Despite such pioneering works, lead-free double perovskite halides with better crystallinity are still in demand for applications to novel optoelectronic devices. Here, we realized highly crystalline Cs2AgBiBr6 single crystals with a well-defined atomic ordering on the microscopic scale. We avoided the formation of Ag vacancies and the subsequent secondary Cs3Bi2Br9 by manipulating the initial chemical environments in hydrothermal synthesis. The suppression of Ag vacancies allows us to reduce the trap density in the as-grown crystals and to enhance the carrier mobility further. Our design strategy is applicable for fabricating other lead-free halide materials with high crystallinity.
