Editorial Feature

Silicon Dioxide (SiO2) Nanoparticles – Properties & Applications

Image Credits: Meletios Verras/shutterstock.com

Silicon dioxide nanoparticles, also known as silica nanoparticles or nano-silica, are the basis for a great deal of biomedical research due to their stability, low toxicity and ability to be functionalized with a range of molecules and polymers.

Nano-silica particles are divided into P-type and S-type according to their structure. The P-type particles are characterized by numerous nanopores, which have a pore rate of 0.61 ml/g and exhibit a higher ultraviolet reflectivity compared to the S-type; the latter also has a comparatively smaller surface area.

Chemical Properties

Chemical Data

Chemical symbol SiO2
CAS No 7631-86-9
Group Silicon 14
Oxygen 16
Electronic configuration Silicon [Ne] 3s2 3p2
Oxygen [He] 2s2 2p4

Chemical Composition


Content (%)

Silicon 46.83
Oxygen 53.33

Physical Properties

Silicon dioxide nanoparticles appear in the form of a white powder. The table below provides the physical properties of these nanoparticles.




Density 2.4 g/cm3 0.086 lb/in3
Molar Mass 59.96 g/mol -

Thermal Properties

Properties Metric Imperial
Melting Point 1600°C 2912°F
Boling Point 2230°C 4046°F


The chief applications of silica nanoparticles are as an additive for the manufacture of rubber and plastics; as a strengthening filler for concrete and other construction composites; and as a stable, non-toxic platform for biomedical applications such as drug delivery and theranostics.

This article was updated on the 11th September, 2019.


  1. Daniel E. Martinez Daniel E. Martinez Mexico says:

    This type of nanoparticles, still has the piezoelctric property

  2. hassan javid hassan javid Islamic Republic of Pakistan says:

    is nano silica harmful as nanofluid in machining setup?

The opinions expressed here are the views of the writer and do not necessarily reflect the views and opinions of AZoNano.com.

Tell Us What You Think

Do you have a review, update or anything you would like to add to this article?

Leave your feedback
Your comment type