(296d) Photocatalytic Inorganic Core Hedgehog Particles

In order to disperse inorganic catalytic nanoparticles in apolar media, chemical camouflage is required for dispersion stability, which greatly reduces catalytic activity. Due to this barrier, there has been little investigation of inorganic catalysts in apolar solvents. This study seeks to create functional catalysts utilizing surface corrugation to circumvent this requirement. Hedgehog Particles (HPs) recently developed in the Kotov lab are polystyrene microparticles with nanoscale zinc oxide spikes which result in marked reduction of Van der Waals interactions and enable dispersion in both polar and nonpolar solvents. HPs have been expanded to inert and active inorganic core materials including silica and hematite by utilizing layer-by-layer polyelectrolyte films. The inorganic core HPs maintain dispersion in a wide array of nonpolar environments and exhibit superior chemical stability and thermal stability. Inorganic HPs display enhanced photocatalytic activity compared to nanorods in the degradation of methylene blue in water. Additionally, photocatalytic activity in chloroform is achieved by the templating of zinc oxide spikes to form titanium dioxide spikes indicating promise for use in nonpolar processes such as cyclohexane oxidation. Inorganic core HPs represent a new family of dispersible catalysts in nonpolar environments.