Synthesis and plasmon-induced charge-transfer properties of monodisperse gold-doped titania microspheres.
Monodisperse gold-doped titania microspheres have been synthesized under high concentration of a titanium precursor (9.34 mM) by introducing a trace amount of chloroauric acid (CA) into the reaction system; the size of the microspheres can be easily tuned (from approximately 587 to approximately 392 nm) by varying the amount of the CA added. The plausible formation mechanism has been discussed in detail. Chloroauric acid was found to act as the stabilizing agent to induce the formation of monodisperse colloidal spheres. Gold-doped anatase titania spheres with approximately 7 nm gold nanodots on the surface were synthesized by calcination. Interestingly, results from surface photocurrent, surface photovoltage, and transient photovoltage measurements indicate that the gold nanodots exhibit different electronic properties when the gold-doped anatase titania spheres were illuminated by different wavelengths of light: one is an electron acceptor in the UV region, while the other is an electron donor in the visible region. Furthermore, the decay time of the injected plasmon-induced electrons was found to be on the millisecond timescale and increased with increasing amounts of gold doped.
Wang
Ping
P
Alan G. MacDiarmid Institute, College of Chemistry, Jilin University, Changchun 130012, China.
Xie
Teng-Feng
TF
Li
Hai-Yan
HY
Peng
Liang
L
Zhang
Yu
Y
Wu
Tong-Shun
TS
Pang
Shan
S
Zhao
Yun-Feng
YF
Wang
De-Jun
DJ