Measurement of sub-2 nm stable clusters during silane pyrolysis in a furnace aerosol reactor

Miguel Vazquez-Pufleau; Yang Wang; Pratim Biswas; Elijah Thimsen

doi:10.1063/1.5124996

Measurement of sub-2 nm stable clusters during silane pyrolysis in a furnace aerosol reactor

J Chem Phys. 2020 Jan 14;152(2):024304. doi: 10.1063/1.5124996.

Authors

Miguel Vazquez-Pufleau¹, Yang Wang¹, Pratim Biswas¹, Elijah Thimsen²

Affiliations

¹ Aerosol and Air Quality Research Laboratory, Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA.
² Interface Research Group, Department of Energy, Environmental & Chemical Engineering, Washington University in St. Louis, St. Louis, Missouri 63130, USA.

PMID: 31941338
DOI: 10.1063/1.5124996

Abstract

The initial stages of particle formation are important in several industrial and environmental systems; however, the phenomenon is not completely understood due to the inability to measure cluster size distributions. A high resolution differential mobility analyzer with an electrometer was used to map out the early stages of Si particle formation from pyrolysis of SiH₄ in a furnace aerosol reactor. We detected for the first time subnanometer stable clusters from silane pyrolysis, and the diameter was measured to be about 0.7 nm. This diameter is within the range of probable sizes that the reported families of critical silane clusters could have based on their actual molecular structure. The size distributions of negative clusters are also mapped out. In addition, gas chromatography mass spectrometry, and transmission electron microscopy characterizations of the clusters and primary particles are used to assess their mechanistic roles in aerosol dynamics of the initial stages of particle formation.