纳米银粒子的发光特性研究

研究了不同粒径和表面修饰的纳米银粒子的发光特性。研究结果表明，在不同波长光激发下，纳米银粒子在362 nm附近出现较强的发射峰，592和725 nm附近出现较弱的发射峰。随着激发光波长增加，发射峰强度下降，362 nm附近的发射峰红移。纳米银颗粒对210 nm的激发光最为敏感。发射峰波长与纳米银粒子表面修饰状态和颗粒尺寸关系不大，只是随着颗粒尺寸的减小，发射峰强度下降。随着狭缝宽度的减小，发射峰强度下降。随着纳米银胶浓度减少，发射峰逐渐聚拢合并为426 nm的单峰，且发射峰的强度先增强后逐渐下降。通过纳米银粒子表面光电子的吸收-再发射和表面能级杂化探讨了纳米银粒子的发光机理。

Photoluminescence of Silver Nanoparticles

In the present paper, the photoluminescence of silver nanoparticles with different size and surface modifier was studied. The results show that the strong emission peak at 362 nm and the two weak emission peaks at 592 and 725 nm respectively were observed by excitation at different wavelengths. With increasing excitation wavelength, the intensity of emission peak decreased and the emission peak at 362 nm red-shifted. Otherwise, the photoluminescence of silver nanoparticles was sensitive to the excitation light of 210 nm. The emission peak has little relation with the surface modification and particle size of silver nanoparticles, just as the particle size decreased, the intensity of peak decreased. The intensity of emission peak decreased with the slit width decreased. The emission peaks gradually gathered together and merged into single peak at 426 nm, and the intensity first increased and then decreased. The mechanism of photoluminescence of silver nanoparticles was discussed by absorption-reemission of photoelectrons and interface energy hybridization.