Surface micro/nanostructure evolution of Au-Ag alloy nanoplates： Synthesis, simulation, plasmonic photothermal and surface-enhanced Raman scattering applications  

作　　者：Hongmei Qian Meng Xu Xiaowei Li Muwei Ji Lei Cheng Anwer Shoaib Jiajia Liu Lan Jiang Hesun Zhu Jiatao Zhang 

机构地区：[1]Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications, School of Materials Science & Engineering, Bei]ing Institute of Technology, Bei]ing 100081, China [2]Laser Micro/Nano-Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China

出　　处：《Nano Research》2016年第3期876-885,共10页纳米研究（英文版）

基　　金：This work was supported by the National Natural Science Foundation of China （Nos. 91323301, 21322105, and 51372025）, the Research Fund for the Doctoral Program of Higher Education of China （No. 2011101120016） and Program for New Century Excellent Talents in University （No. NCET-11-0793）. The authors would like to thank Prof. Chen Wang and Prof. Yanjun Guo of National Center for Nanoscience and Technology, China for AFM and SERS measure- ments and helpful discussions, respectively; Dr. Haiwei Li for help on BET tests and helpful discussions.

摘　　要：This study reports the controllable surface roughening of Au-Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuC14 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, surface- roughened 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.This study reports the controllable surface roughening of Au-Ag alloy nanoplates via the galvanic replacement reaction between single-crystalline triangular Ag nanoplates and HAuC14 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, surface- roughened 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.

关 键 词：Au-Ag alloy nanoplates surface roughening finite element method（FEM） simulation PHOTOTHERMAL surface enhanced Ramanscattering （SERS） 

分 类 号：O657.37[理学—分析化学] TB383[理学—化学]