posted on 2022-08-04, 12:40authored byChunyuan Liang, Duanjun Sun, Hao Lv, Wen Chu, Yu Duan, Yeqiang Bu, Jiabin Liu, Hongtao Wang
The performance degradation via sintering phenomenon
is a critical
issue for the application of supported nanoparticles in industrial
catalysis. However, the challenges to combine in situ stimulation
and three-dimensional (3D) characterization hinder a profound understanding
of sintering behaviors, thus the effect of spatial location on nanoparticles
sintering has long been neglected. Herein, based on a homemade holder
integrated with in situ Joule heating and electron tomography, a quasi-four-dimensional
(4D) transmission electron microscope characterization approach is
developed to reveal the spatial location of supported nanoparticles
and its pronounced impact on size distribution and sintering behaviors.
The results of 3D visualization and statistical analysis demonstrate
a strong location-dependent sintering behavior of supported nanoparticles,
where external nanoparticles sinter via migration coalescence, and
internal nanoparticles sinter via Ostwald ripening. The quasi-4D methods
developed in this work can also be extended to the study on 3D configuration
evolution of other nanomaterials under an external stimulus.