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Updated: Aug 22, 2025
06:52
Synthesis of Esters Via a Greener Steglich Esterification in Acetonitrile
Published on: October 30, 2018
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Modifying the Stöber Process: Is the Organic Solvent Indispensable?
Jinxin Wang1, Kaimin Zhang1, Safiyye Kavak2
1Department of Chemistry, University of Antwerp, Universiteitsplein 1, 2610, Antwerpen, Belgium.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|November 7, 2022
Summary
Researchers found that organic solvents are not essential for the Stöber method synthesis of silica spheres. An immiscible synthesis method was developed, enabling solvent-free production of uniform silica nanoparticles.
Area of Science:
- Materials Science
- Nanotechnology
- Inorganic Chemistry
Background:
- The Stöber method is a foundational technique for synthesizing inorganic nanomaterials.
- A significant drawback of the Stöber method is its reliance on substantial quantities of organic solvents.
Purpose of the Study:
- To investigate the possibility of omitting organic solvents in the Stöber method.
- To develop an alternative synthesis route for silica particles without organic solvents.
Main Methods:
- Exploration of ethanol's role in the Stöber synthesis of silica spheres.
- Development of an initially immiscible synthesis method as a replacement for the organic solvent-based Stöber process.
Main Results:
- Ethanol, while influencing particle size and uniformity, was found not to be indispensable.
- A novel immiscible synthesis method successfully produced silica particles in the same size range as the traditional Stöber process, without organic solvents.
Conclusions:
- Organic solvents can be omitted from the Stöber synthesis of silica particles.
- The newly discovered immiscible synthesis method offers a greener alternative for silica nanoparticle production.
- This solvent-free approach holds potential for broader applications in synthesizing other Stöber-based materials.
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