还原气氛退火对Ag-Cu纳米颗粒光学吸收的影响

还原气氛退火对Ag-Cu纳米颗粒光学吸收的影响 Influence of Reducing Annealing Atmosphere on Ag and Cu Nanoclusters Produced by Sequential Ion Implantation in Silica 任峰 REN Feng 1 2 first-author 陈海波 CHENG Hai-bo 1 2 蒋昌忠 JIANG Chang-zhong 1 2 张丽 ZHANG Li 1 2 石瑛 SHI Ying 1 2 武汉大学物理科学与技术学院 武汉大学物理科学与技术学院 School of Physics and Technology, Wuhan University School of Physics and Technology, Wuhan University 武汉大学物理科学与技术学院,湖北,武汉,430072 武汉大学物理科学与技术学院,湖北,武汉,430072 经43kV和30kV加速后的Ag、Cu离子按相同的剂量在室温下先后注入到非晶SiO2玻璃.用X射线光电子能谱（XPS）分析注入样品的价态分布,发现Ag、Cu仍以金属态形式存在.注入后光学吸收谱显示吸收峰的位置在442nm,说明在该实验条件下,SiO2玻璃表层很有可能形成了Ag Cu纳米合金颗粒.样品在还原气氛下从300～800℃每隔100℃退火1h后,发现等离子体共振吸收峰的位置发生了蓝移并在500℃时出现双峰,表明退火过程中Ag Cu纳米合金颗粒开始分解成Ag和Cu纳米颗粒.随着退火温度的上升,Ag、Cu纳米颗粒生核生长,当退火温度高于600℃时Cu颗粒尺寸变小,当退火温度高于700℃时Ag颗粒才开始变小. Ag and Cu ions have been sequential implanted into silica at room temperature with energy of 43 keV and 30 keV respectively. X-ray photoelectron spectra （XPS） analysis the value states of Ag and Cu in the implanted composite sample, the results show that Ag and Cu exist in the form of metal state. The optical absorption spectra indicates there is only a single surface plasmon resonance （SPR） peak at 442 nm before annealing, which shows the Ag-Cu binary alloy nanoclusters have been formed. After annealing for 1 hour at different temperature from 300℃ to 800℃ with intervals of 100℃, the SPR peaks show a blue shift and two peaks appear when the annealing temperature reaches 500℃ which attributes to the decomposion of alloy nanoclusters and formation of Ag and Cu nanoclusters. Applying the free electron model of metal particles, we calculate average sizes of nanoparticles in the different annealing temperatures, the results show that the sizes of nanoparticles increase gradually with increasing temperature. When the temperature is higher than 600℃ for Cu and 700℃ for Ag, the size becomes smaller, because at high temperatures Ag and Cu migrates to the sample surface and disappears from the surface. 金属离子注入 还原气氛退火 纳米颗粒 表面等离子体共振吸收 蓝移 metal ion implantation reducing annealing nanoclusters surface plasmon resonance absorption blue shift TB383 国家自然科学基金资助项目（10005005） 2003-05-01 2021-04-01 5