摘要
通过45 keV,1.0×1017cm-2的Cu离子注入SiO2基底合成了嵌入式的Cu纳米颗粒,采用不同剂量的50 keV Zn离子对Cu纳米颗粒进行后续辐照,详细研究了Zn离子后续辐照对Cu纳米颗粒结构、光学性质的影响及其氧气气氛下的热演变规律.研究结果表明,Cu和0.5×1017cm-2的Zn离子顺次注入可在SiO2基底中形成Cu-Zn合金纳米颗粒,它们可以在516 nm附近引起独特的表面等离子共振(SPR)吸收峰.后续O2气氛中450?C退火可以导致Cu-Zn合金纳米颗粒分解,并在基体中形成了ZnO和Cu纳米颗粒.研究结果还表明后续Zn离子的辐照可以有效地提高Cu纳米颗粒的抗氧化能力;同时基体中Cu的存在也会加速Zn向样品表面的扩散,从而促进了ZnO的形成.
Cu nanoparticles （NPs） embedded in silica were synthesized by implantation of 45 keV Cu ions at a fluence of 1.0×l017 cm-2, and then subjected to post irradiation with 50 keV Zn ions at ituences of 0.5×1017 cm-2 and 1.0-1017 cm-2, respectively. Zn post ion implantation induced modifications in structures, optical absorption properties of Cu NPs as well as their thermal stability in oxygen ambient have been investigated in detail. Results clearly show that Cu-Zn alloy NPs could be formed in the Cu pre-implanted silica followed by Zn ion irradiation at a fluence of 0.5× 1017 cm-2, which causes an unique surface plasmon resonance （SPR） absorption peak at about 516 nm. Subsequent annealing in oxygen atmosphere results in the decomposition of Cu-Zn alloy NPs, at 450 ℃, and thus, ZnO and Cu NPs appear in the substrate. Further increase of annealing temperature to 550 ℃ could transform all the Zn and Cu into ZnO and CuO. Moreover, results also demonstrate that introduction of Zn into SiO2 substrate could effectively suppress the oxidation of Cu NPs, meanwhile, the existence of Cu could promote thermal diffusion of Zn towards substrate surface, which enhances the oxidation of Zn. The underlying mechanism has been discussed.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2014年第7期383-390,共8页
Acta Physica Sinica
基金
国家自然科学基金(批准号:11175129,11175235)
天津市自然科学基金(批准号:12JCZDJC26900)资助的课题~~
关键词
双离子注入
Cu—Zn合金纳米颗粒
热稳定性
Zn扩散
sequential ion implantation, Cu-Zn alloy nanoparticles, thermal stability, diffusion of Znatoms
