Song Kepeng, Liu Jiakai, Qi Dongqing, Lu Ning, Qin Wei
School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, China.
Suzhou Research Institute, Shandong University, Suzhou 215123, China.
J Phys Chem Lett. 2022 Mar 10;13(9):2117-2123. doi: 10.1021/acs.jpclett.2c00210. Epub 2022 Feb 28.
Ultrastable CsPbBr nanoplates against electron beam irradiations are fabricated and nanodomains with anomalous high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) contrasts are observed within CsPbBr nanoplates. Atomic resolution energy dispersive X-ray spectroscopy (EDS) mapping, which requires even higher beam currents and may cause significant damages on electron beam sensitive materials, are obtained without any detectable damages or decomposition. Combining HAADF-STEM images, atomic resolution EDS mapping, and image simulations has revealed detailed structure and chemistry of the nanodomains to be induced by Ruddlesden-Popper faults (RP faults) rather than any chemical intermixing or formation of new phases. A formation mechanism is also proposed on the basis of the atomic structure of the nanodomains. This result promotes an atomic-level understanding of inorganic lead halide perovskites and may help to reveal their structure-property relationship.
制备了抗电子束辐照的超稳定CsPbBr纳米片，并在CsPbBr纳米片中观察到具有异常高角度环形暗场扫描透射电子显微镜（HAADF-STEM）对比度的纳米域。获得了原子分辨率能量色散X射线光谱（EDS）图谱，该图谱需要更高的束流，并且可能对电子束敏感材料造成显著损伤，但未观察到任何可检测到的损伤或分解。结合HAADF-STEM图像、原子分辨率EDS图谱和图像模拟，揭示了由Ruddlesden-Popper断层（RP断层）而非任何化学混合或新相形成所诱导的纳米域的详细结构和化学性质。还基于纳米域的原子结构提出了一种形成机制。这一结果促进了对无机卤化铅钙钛矿的原子级理解，并可能有助于揭示它们的结构-性能关系。
