Surface micro/nanostructure evolution of Au–Ag alloy nanoplates: Synthesis, simulation, plasmonic photothermal and surface-enhanced Raman scattering applications
Au–Ag alloy nanoplates, surface roughening, finite element method (FEM) simulation, photothermal, surface enhanced Raman scattering (SERS)
This study reports the controllable surface roughening of Au–Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuCl4 in an aqueous medium. With a combination of experimental evidence and finite element method (FEM) simulations, improved electromagnetic field (E-field) enhancement around the surface-roughened Au– Ag nanoplates and tunable light absorption in the near-infrared (NIR) region (~800–1,400 nm) are achieved by the synergistic effects of the localized surface plasmon resonance (LSPR) from the maintained triangular shape, the controllable Au–Ag alloy composition, and the increased surface roughness. The NIR light extinction enables an active photothermal effect as well as a high photothermal conversion efficiency (78.5%). The well-maintained triangular shape, surfaceroughened evolutions of both micro- and nanostructures, and tunable NIR surface plasmon resonance effect enable potential applications of the Au–Ag alloy nanoplates in surface-enhanced Raman spectroscopic detection of biomolecules through 785-nm laser excitation.
Tsinghua University Press
Hongmei Qian,Meng Xu,Xiaowei Li,Muwei Ji,Lei Cheng,Anwer Shoaib,Jiajia Liu,Lan Jiang,Hesun Zhu,Jiatao Zhang, Surface micro/nanostructure evolution of Au–Ag alloy nanoplates: Synthesis, simulation, plasmonic photothermal and surface-enhanced Raman scattering applications. NanoRes.2016, 9(3): 876–885