Nucleation Site Distribution Probed by Phase-Enhanced Environmental Scanning Electron Microscopy
Lenan Zhang, Ryuichi Iwata, Lin Zhao, Shuai Gong, Zhengmao Lu, Zhenyuan Xu, Yang Zhong, Jinlong Zhu, Samuel Cruz, Kyle L. Wilke, Ping Cheng, Evelyn N. Wang
Abstract
Nucleation site distribution is ubiquitous in many natural and industrial processes, such as liquid-to-vapor phase change, gas-evolving reactions, and solid-state material growth. However, a comprehensive understanding of nucleation site distribution remains elusive. These limitations are due to the challenge of probing micro/nanoscopic nucleation sites and inadequate statistical interpretation of the nucleation process. Here we report direct experimental observation of nucleation site distribution in droplet condensation using phase-enhanced environmental scanning electron microscopy. We also use statistical theory to demonstrate that the population of nucleation sites is governed by the Poisson distribution, whereas the nearest-neighbor distance follows the Rayleigh distribution instead of the commonly used Poisson distribution. We further show the broad applicability of these insights into nucleation site distribution to hydrogen-evolving reactions and chemical vapor deposition. Our platform, combining precise characterization and theory, advances the fundamental understanding of nucleation phenomena and guides designs from materials to devices.