摘要
通过溶胶-凝胶法,制备了银/二氧化硅核壳材料(Ag@SiO2),对SiO2壳层厚度进行了有效调控,并系统研究了壳层厚度对银的等离子体共振峰(LSPR)以及对折射率灵敏度(RIS)的影响。研究结果表明,随SiO2壳层包覆厚度的增加,银纳米颗粒的LSPR吸收峰呈现先红移后蓝移的规律。对于粒径为50 nm的银纳米颗粒,当SiO2壳层达到65 nm时,LSPR最大吸收波长为465 nm。进一步增加SiO2壳层厚度,LSPR发生蓝移并且强度变弱,当SiO2壳层达到120 nm时,LSPR吸收峰已无法清晰辨认。研究了Ag@SiO2材料的RIS效应,发现随着SiO2厚度的增大RIS效应逐渐变小。
Silver/silica composite core-shell nanoparticles （Ag@ SiO2 ） with different silica shell thickness were prepared by sol-gel technology. Their localized surface plasmon resonance （LSPR） properties and refractive index sensitivities（RIS） were studied. With increasing of silica shell thickness, LSPR peak first got a red-shift. When silica shell thickness was 65 nm, the maximal shift about 50 nm had been reached. With further increase of shell thickness, LSPR peak shown blue-shift. LSPR peak became illegible when the shell thickness reached 120 nm. We also observed that RIS of silver nanopartieles decreased with increasing shell thickness.
出处
《应用化学》
CAS
CSCD
北大核心
2014年第3期323-327,共5页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(20873136)资助项目~~
关键词
银纳米
二氧化硅
核壳结构
等离子体吸收峰
折射率灵敏度
silver nanoparticles, silica, core-shell, localized surface plasmon resonance, refractive index sensitivities
