Patent · US Expired

Method of making silica nanoparticles

US5770022A · kind A · utility

59Cited by
4References
9Claims
0Family size

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Key dates

Filing dateJun 5, 1997
Grant dateJun 23, 1998
Priority date
Expiry dateJun 5, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/2993
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A method of making silicon oxide nanoparticles possessing photoluminescence in the blue and green part of the visible spectrum when irradiated with ultraviolet (UV) light. The silicon oxide nanoparticles are formed in a chamber containing a direct current (dc) electric arc that generates a plasma in an oxygen-containing atmosphere. In the chamber, silicon is used as the anode, and the cathode can be copper (Cu) or tungsten (W). The use of silicon as an electrode is enabled by doping silicon with boron to a sufficiently high electronic conductivity, and orienting the two electrodes vertically in the chamber, so that the silicon anode is lowermost to contain silicon in the anode when it melts and vaporizes in the arc. The silicon oxide nanoparticles are collected on a cold plate adjacent to the arc.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.