Colloidal Synthesis

Facilities are available in our department for colloidal synthesis of nanoparticles (NPs). In particular, the inverse micelle encapsulation technique is used for the synthesis of monodisperse NPs. In this method, poly(styrene-b-2-vinyl pyridine) diblock copolymers are dissolved in toluene to form inverse micelles.

micelle

Next, metal salts are added to the solution to form metal NPs within the micelles. As shown below, the micellar NPs can be either dipcoated onto planar supports to form a monolayer of hexagonally arranged model NPs, or they can be deposited onto high surface area supports to prepare real catalysts for reactivity studies. The polymer can be removed using either an O2 plasma or O2 annealing treatment. NP size and shape can be tuned by varing the molecular weight of the P2VP polymer core, or by varying the ratio of metal to P2VP. The interparticle distance can also be tuned by varying the molecular weight of the PS polymer tail.

synthesis

 

The following instruments are available for colloidal synthesis of NPs:

Braun LABstar Glove Box Workstation

  • Ingegrated purifier unit
  • Removal of oxygen and moisture, < 1 ppm
  • Negative or positive pressure operation
  • PLC-M. Braun controller

SPI Plasma Prep III Plasma Etcher

  • 1-100 W power
  • 4" diameter x 6" depth Quartz Chamber
  • SPI Plasma Prep III Process Controller
    • Gas flow rate control for plasma pressure adjustment
    • Proportional mixing of two input gases
    • Plamsa process timer

spi plasma