Xiong Hao, Wang Yi-Chi, Liang Xiaoyu, Zhao Mingyu, Tian Guo, Wang Guowei, Gu Lin, Chen Xiao, Wei Fei
Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084, China.
Beijing National Center for Electron Microscopy and Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China.
J Am Chem Soc. 2025 Aug 13;147(32):28965-28972. doi: 10.1021/jacs.5c07054. Epub 2025 Jul 31.
Accurate assessment of molecular uptake and interactions at pore surfaces is crucial for advancing functional porous materials. However, these processes are governed by the intricate interplay of geometry constraints, local electric fields, and operational conditions, requiring in situ atomic-resolution characterization. Here, we present sub-angstrom-resolution (0.76 Å) and linear-phase-response imaging of zeolites and adsorbed benzene molecules across varying atmospheric conditions using in situ electron ptychography. Environment-induced crystal mis-tilts and low electron beam coherence were effectively corrected to maintain high resolution. We established a linear relationship between image phase changes and the number of adsorbed molecules, enabling molecule quantification within individual pores under varying benzene vapor pressures. Depth analysis revealed nonuniform molecular adsorption along pore channels, with guest molecules preferentially accumulated near Al-enriched regions. Our findings provide a general strategy for investigating localized molecular behaviors on the atomic scale in complex environments relevant to industrial catalysis and separation processes.
准确评估孔表面的分子摄取和相互作用对于推进功能性多孔材料至关重要。然而，这些过程受几何约束、局部电场和操作条件的复杂相互作用支配，需要原位原子分辨率表征。在此，我们使用原位电子叠层成像技术，在不同大气条件下对沸石和吸附的苯分子进行了亚埃分辨率（0.76 Å）和线性相位响应成像。有效校正了环境引起的晶体微倾斜和低电子束相干性，以保持高分辨率。我们建立了图像相位变化与吸附分子数量之间的线性关系，从而能够在不同苯蒸气压下对单个孔内的分子进行定量。深度分析揭示了沿孔道的分子吸附不均匀，客体分子优先聚集在富铝区域附近。我们的研究结果为在与工业催化和分离过程相关的复杂环境中，在原子尺度上研究局部分子行为提供了一种通用策略。
