Research Seminar of Dr. WANG Feng fromCity University of Hong Kong

Lecture Time: 09:30 on 15th June, 2016

Lecture Room: 316 of Chemical Laboratory Building

Lecture Title:Rational Photon Upconversion in Core-Shell Nanoparticles

WANG Feng

Department of Physics and Materials Science

City University of Hong Kong

Abstract

Spectral conversion of light radiation is essential for a variety of modern-day technologies including displays, photovoltaics, data storage, and cancer therapy. In the past decades, a variety of luminescent materials, including organic dyes and semiconductor quantum dots, were developed to realize photon energy conversion in the ultraviolet (UV) to near infrared (NIR) spectral range. However, practical application of these techniques is typically limited by constraints such as toxicity and/or poor stability. In this context, lanthanide-doped upconversion nanoparticles have been developed as a promising alternative to conventional luminescent nanomaterials. By comparison, these nanoparticles offer low cytotoxicity, sharp emission peaks, long-lived excited electronic states, as well as high stability against photo bleaching and chemical degradation. In this talk, I focus on our recent efforts on lanthanide-doped core-shell nanoparticles that are generally composed of a layer-by-layer structure with a set of lanthanide ions incorporated into separate layer. I discuss how to fabricate these nanostructures by wet-chemistry method and how to characterize the nanostructure by a combination of electron microscopy and luminescence spectroscopy. Examples will be given to demonstrate how to enhance multiphoton upconversion emissions for exciting new technological applications.

References:

1. X. Chen, D. Peng, Q. Ju, F. Wang*, Photon upconversion in core-shell nanoparticles. Chem. Soc. Rev. 2015, 44, 1318.
2. B. Chen, D. Peng, X. Chen, X. Qiao, X. Fan, F. Wang*, Establishing the Structural Integrity of Core–Shell Nanoparticles against Elemental Migration using Luminescent Lanthanide Probes, Angew. Chem. Int. Ed. 2015, 54, 12788.
3. X. Chen, L. Jin, W. Kong, T. Sun, W. Zhang, X. Liu, J. Fan, S. F. Yu*, Feng Wang*, Confining energy migration in upconversion nanoparticles towards deep ultraviolet lasing, Nature Communications 2016, 7, 10304, doi: 10.1038/ncomms10304...

Biography

Dr. Feng Wang is an assistant professor in the Department of Physics and Materials Science at City University of Hong Kong. He received his BE (2001) and PhD (2006) degrees in Materials Science and Engineering from Zhejiang University. His PhD thesis was focused on the synthesis and characterization of lanthanide-doped fluoride nanomaterials under the supervision of Prof. Minquan Wang and Prof. Xianping Fan. He then carried out postdoctoral research work with Prof. Xiaogang Liu at the National University of Singapore and the Institute of Materials Research and Engineering in Singapore. He joined the faculty of City University of Hong Kong in 2012. His research interests include the design, synthesis, mechanistic investigation, and application of luminescent nanomaterials.