Wu Pae C, Khoury Christopher G, Kim Tong-Ho, Yang Yang, Losurdo Maria, Bianco Giuseppe V, Vo-Dinh Tuan, Brown April S, Everitt Henry O
Department of Electrical and Computer Engineering, Duke University, Durham, North Carolina 27708, USA.
J Am Chem Soc. 2009 Sep 2;131(34):12032-3. doi: 10.1021/ja903321z.
Size-controlled gallium nanoparticles deposited on sapphire were explored as alternative substrates to enhance Raman spectral signatures. Gallium's resilience following oxidation is inherently advantageous in comparison with silver for practical ex vacuo nonsolution applications. Ga nanoparticles were grown using a simple molecular beam epitaxy-based fabrication protocol, and monitoring their corresponding surface plasmon resonance energy through in situ spectroscopic ellipsometry allowed the nanoparticles to be easily controlled for size. The Raman spectra obtained from cresyl fast violet (CFV) deposited on substrates with differing mean nanoparticle sizes represent the first demonstration of enhanced Raman signals from reproducibly tunable self-assembled Ga nanoparticles. Nonoptimized aggregate enhancement factors of approximately 80 were observed from the substrate with the smallest Ga nanoparticles for CFV dye solutions down to a dilution of 10 ppm.
研究了沉积在蓝宝石上的尺寸可控的镓纳米颗粒作为增强拉曼光谱特征的替代衬底。与银相比，镓在氧化后的韧性对于实际的真空非溶液应用具有固有的优势。使用基于简单分子束外延的制造协议生长镓纳米颗粒，并通过原位光谱椭偏仪监测其相应的表面等离子体共振能量，从而能够轻松控制纳米颗粒的尺寸。从沉积在具有不同平均纳米颗粒尺寸的衬底上的甲酚紫（CFV）获得的拉曼光谱首次证明了来自可重复调谐的自组装镓纳米颗粒的增强拉曼信号。对于稀释至10 ppm的CFV染料溶液，从具有最小镓纳米颗粒的衬底观察到约80的未优化聚集增强因子。
