Nanoparticle Chemistry

• 1nm =


  10^-9 m
• Size of nanoparticles


  1-100nm in size
• Bulk material


  Not a nanoparticle
• The smaller a particle


  the larger the surface area to volume ratio

  
• As a cube decreases in size by a factor of 10


  Its surface area:volume ratio increases by a factor of 10
• Nanoparticles have different properties to bulk materials because


  Most atoms are at the surface and they have a high surface area to volume ratio
• Uses of nanoparticles


  Catalysts, in electronics, in sunscreens.

  
• Advantages of nanoparticles in sunscreen


  Better coverage, more effective protection from UV

  
• Disadvantages of nanoparticles in sunscreen

  Small enough to enter the bloodstream, could damage cells, could damage the environment

  
• Number of atoms in a nanoparticle


  A few hundred atoms
• Risks of nanoparticles are unknown

  They have not been used for very long
• Properties of nanoparticles


  Very different to bulk material