TY - GEN
T1 - One-dimensional plasmonic nano-photocatalysts
T2 - Solar Hydrogen and Nanotechnology VI
AU - Hunyadi Murph, Simona E.
PY - 2011
Y1 - 2011
N2 - This study describes a simple two-step approach to coat gold nanorods with a silica/titania shell. Gold nanorods with an aspect ratio of 2.5 (L=48±2 and d=19±1) are synthesized by a silver-seed mediated growth approach according to our previously reported procedure (Hunyadi Murph ACS Symposium Series, Volume 1064, Chapter 8, 2011, 127-163 and reference herein). Gold nanorods are grown on pre-formed gold nano-seeds in the presence of surfactant, cetyltrimethylammonium bromide (CTAB), and a small amount of silver ions. A bifunctional linker molecule which has a thiol group at one end and a silane group at the other is used to derivatize gold nanorods. The silane group is subsequently reacted with both sodium silicate and titanium isopropoxide to a silica/titania shell around the gold nanorods. By fine tuning the reaction conditions, the silica/titania shell thickness can be controlled from ∼5 to ∼40nm. The resulting nanomaterials are stable, amenable to scale up and can be isolated without core aggregation or decomposition. These new materials have been characterized by scanning electron microscopy, energy dispersive X-ray analysis, UV-Vis spectroscopy and dynamic light scattering analysis. Photocatalytic activity of Au-silica/titania nanomaterials under visible and UV illumination is measured via degradation of a model dye, methyl orange (MO) under visible and UV illumination. The results indicate a 3 fold improvement in the photocatalytic decomposition rate of MO under visible illumination vs. UV illumination.
AB - This study describes a simple two-step approach to coat gold nanorods with a silica/titania shell. Gold nanorods with an aspect ratio of 2.5 (L=48±2 and d=19±1) are synthesized by a silver-seed mediated growth approach according to our previously reported procedure (Hunyadi Murph ACS Symposium Series, Volume 1064, Chapter 8, 2011, 127-163 and reference herein). Gold nanorods are grown on pre-formed gold nano-seeds in the presence of surfactant, cetyltrimethylammonium bromide (CTAB), and a small amount of silver ions. A bifunctional linker molecule which has a thiol group at one end and a silane group at the other is used to derivatize gold nanorods. The silane group is subsequently reacted with both sodium silicate and titanium isopropoxide to a silica/titania shell around the gold nanorods. By fine tuning the reaction conditions, the silica/titania shell thickness can be controlled from ∼5 to ∼40nm. The resulting nanomaterials are stable, amenable to scale up and can be isolated without core aggregation or decomposition. These new materials have been characterized by scanning electron microscopy, energy dispersive X-ray analysis, UV-Vis spectroscopy and dynamic light scattering analysis. Photocatalytic activity of Au-silica/titania nanomaterials under visible and UV illumination is measured via degradation of a model dye, methyl orange (MO) under visible and UV illumination. The results indicate a 3 fold improvement in the photocatalytic decomposition rate of MO under visible illumination vs. UV illumination.
KW - anisotropic nanophotocatalysts
KW - core-shell
KW - gold-titania
KW - titania.
UR - http://www.scopus.com/inward/record.url?scp=80053518429&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80053518429&partnerID=8YFLogxK
U2 - 10.1117/12.893029
DO - 10.1117/12.893029
M3 - Conference contribution
AN - SCOPUS:80053518429
SN - 9780819487193
T3 - Proceedings of SPIE - The International Society for Optical Engineering
BT - Solar Hydrogen and Nanotechnology VI
Y2 - 23 August 2011 through 25 August 2011
ER -