Reference Material Is Smallest Yet

The National Institute of Standards & Technology (NIST) has issued its smallest reference material for confirming measurements of synthetic nanoparticles. Reference Material (RM) 8027 contains silicon nanoparticles that are certified to be approximately 2 nm in diameter suspended in toluene. Created for validating measurements of particles between 1 and 100 nm, the new reference material is particularly useful “for anyone working with nanomaterials at dimensions 5 nm or less,” says Vytas Reipa, leader of the team that developed RM 8027. The nanoparticles were made by etching nanocrystals from a silicon wafer, separating the crystals using ultrasound, and then stabilizing each within an organic shell. Analytical techniques including dynamic light-scattering electron microscopy and inductively coupled plasma mass spectrometry confirmed the size and chemical composition of the reference material, NIST says. Silicon nanoparticles are being studied for use in next-generation photovoltaic solar cells, solid-state lighting, and the cathodes of lithium batteries, the agency adds. The material can be ordered through nist.gov/srm.