Zhao Tiqing, Jiang Youhong, Luo Shiwen, Ying Yifan, Zhang Qian, Tang Shi, Chen Linzhi, Xia Jing, Xue Peng, Zhang Jia-Jun, Sun Shi-Gang, Liao Hong-Gang
State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China.
Xiamen Chip-Nova Technology Co., Ltd., Xiamen 361005, People's Republic of China.
Lab Chip. 2023 Aug 22;23(17):3768-3777. doi: 10.1039/d3lc00184a.
The catalysis reaction mechanism at nano/atomic scale attracted intense attention in the past decades. However, most characterization technologies can only reflect the average information of catalysts, which leads to the inability to characterize the dynamic changes of single nanostructures or active sites under operando conditions, and many micro-nanoscale reaction mechanisms are still unknown. The combination of transmission electron microscopy (TEM) holder system with MEMS chips provides a solution for it, where the design and fabrication of MEMS chips are the key factors. Here, with the aid of finite element simulation, an ultra-stable heating chip was developed, which has an ultra-low thermal drift during temperature heating. Under ambient conditions within TEM, atomic resolution imaging was achieved during the heating process or at high temperature up to 1300 °C. Combined with the developed polymer membrane seal technique and nanofluidic control system, it can realize an adjustable pressure from 0.1 bar to 4 bar gas environment around the sample. By using the developed ultra-low drift gas reaction cells, the nanoparticle's structure evolution at atomic scale was identified during reaction.
在过去几十年中，纳米/原子尺度的催化反应机理引起了广泛关注。然而，大多数表征技术只能反映催化剂的平均信息，这导致无法在实际操作条件下表征单个纳米结构或活性位点的动态变化，许多微纳尺度的反应机理仍然未知。透射电子显微镜（TEM）样品杆系统与微机电系统（MEMS）芯片的结合为解决这一问题提供了一种方案，其中MEMS芯片的设计和制造是关键因素。在此，借助有限元模拟，开发了一种超稳定加热芯片，其在温度加热过程中具有超低的热漂移。在TEM环境条件下，在加热过程中或高达1300℃的高温下实现了原子分辨率成像。结合所开发的聚合物膜密封技术和纳米流体控制系统，可以在样品周围实现0.1巴至4巴的可调压力气体环境。通过使用所开发的超低漂移气体反应池，在反应过程中确定了纳米颗粒在原子尺度上的结构演变。
