Surface-Modified Silicon Nanoparticles with Ultrabright Photoluminescence and Single-Exponential Decay for Nanoscale Fluorescence Lifetime Imaging of Temperature

• Published in: Journal of the American Chemical Society Vol. 135; no. 40; pp. 14924 - 14927
• Main Authors: Li, Qi, He, Yao, Chang, Jian, Wang, Lei, Chen, Hongzheng, Tan, Yan-Wen, Wang, Haiyu, Shao, Zhengzhong
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 09.10.2013
• Subjects: Luminescent Measurements; Nanoparticles - chemistry; Optical Imaging - methods; Silicon - chemistry; Surface Properties; Temperature; Water - chemistry
• ISSN: 0002-7863; 1520-5126
• DOI: 10.1021/ja407508v

In this Communication, we report fabrication of ultrabright water-dispersible silicon nanoparticles (SiNPs) with quantum yields (QYs) up to 75% through a novelly designed chemical surface modification. A simple one-pot surface modification was developed that improves the photoluminescent QYs of SiNPs from 8% to 75% and meanwhile makes SiNPs water-dispersible. Time-correlated single photon counting and femtosecond time-resolved photoluminescence techniques demonstrate the emergence of a single and uncommonly highly emissive recombination channel across the entire NP ensemble induced by surface modification. The extended relatively long fluorescence lifetime (FLT), with a monoexponential decay, makes such surface-modified SiNPs suitable for applications involving lifetime measurements. Experimental results demonstrate that the surface-modified SiNPs can be utilized as an extraordinary nanothermometer through FLT imaging.