Fe2O3 nanopowders are red or reddish-brown and composed of particles between 20 and 40nm, available in alpha and gamma variations.

• Coatings: The unique blend of traits inherent to the different iron oxide nanopowders make them ideal as ingredients in certain coatings, such as magnetic coatings and coatings designed to absorb EM-waves.
• Purification: Iron oxide nanoparticles have a variety of purification-related applications, particularly in biological and waste water contexts.

"Iron Oxide Nanopowder/Nanoparticles(alpha- Fe2O3, 99%, 20-40 nm)" -Retrieved 3/26/2021 from https://ssnano.com/inc/sdetail/iron_oxide_nanoparticles___nanopowder___fe2o3__alpha__99___20_40nm_/308

available online (see '3310DX  Iron Oxide Nanoparticles/Nanopowder MSDS for Download')