Rapid Screening of Nanoporous Structures in SiO2 Catalyst Particles via Helium Ion Microscopy

Porous materials are some of the most important materials in a vast number of applications including biomaterials, medical delivery systems, solar cells and catalysts [1]. However, the number of techniques available to quantify pore size and pore structure in these material systems is limited. The most common technique to quantify porosity is gas absorption; gas absorption produces a global pore size average, and does not reveal any local microscopic or nanoscale information on pore size, distribution, or shape [2]. Electron microscopy is also challenging in imaging these materials, due to charging; and typically necessitates additional sample preparation steps, such as metal coating, or cryogenic preparations – potentially significantly altering the imaged surface.