报告题目：Towards Understanding and Engineering the Optical Properties of

Plasmonic Nanostructures and Hybrid Perovskites

报告时间：2018年1月5日星期五上午10:00

报告地点：吉林大学中心校区物理楼333报告厅

报告人：尹婷婷 博士

报告人单位：南洋理工大学

讲座摘要：

Localized surface plasmon resonance (LSPR) on metallic nanostructures is able to significantly modulate photoluminescence (PL) properties, including emission intensity, peak position and polarization. However, the mechanism for anomalous blue-shifted peak and partial depolarization of PL emission from metallic nanostructures, relative to the corresponding scattering spectra, is still unclear so far.

In the first part of this presentation, the detailed investigations on plasmonic resonance properties from various metallic nanostructures (single gold nanodiscs, dimers and dolmen-like gold nanostructures) and related PL emission characteristics are discussed. These works provide a general solid foundation and guidance for analyzing and manipulating the physical processes of the PL emission from various plasmonic nanostructures.

Hybrid organic-inorganic perovskites (bulk and quantum dots) are of great interest as promising materials for potential applications in solar cells and LEDs, due to their high carrier mobility, tunable spectral absorption range and easy processing. New crystal structures and physical properties of this class materials can be readily developed under high pressure, providing significant insights into pressure-induced structural mechanism and engineering.

In the second part of this presentation, the novel optical properties of three-dimensional (3D) bulk CH3NH3PbBr3 single crystals under high pressure will be discussed. At ~2.3 GPa, photoluminescence intensity is enhanced by ~400 times, and broad emission appear at 4.16 GPa. All structural phases and physical properties are reversible after release. For the CH3NH3PbBr3 nanocrystals (NCs) the pressure-induced sintering of 10 nm into nanoplate of 100 nm is reported. After pressure release, this pressure-developed nanocrystal structure is stable and irreversible with new optical behaviors. For (C4H9NH3)2PbI4 two-dimensional 2D layered perovskite, the structure-property relationship is resolved and established via a comprehensive pressure study. These high-pressure works provide us a mechanistic guideline for synthetically designing novel crystal structures of hybrid perovskites toward stable and long-term photoelectronic and photovoltaic applications in future light emitting devices and clean energy generation.

报告人简介：

Ph.D. candidate 2013 ~ 2017

Major: Optical studies on plasmonic

nanostructures and perovskite materials

Nanyang Technological University, Singapore

Bachelor of Science 2009 ~ 2013

Major: Optical Information Sciences and Technology

Jilin University, China

Research Interests

My research interest (2013-2015) is in fabrication and optical studies of plasmonic nanostructures, focusing on understanding the physical role of the localized surface plasmon resonance (LSPR) on the Photoluminescence emission process and polarization properties from various plasmonic nanostructures.

My research interest (2016-present) is in optical studies of hybrid perovskites, focusing on understanding the physical role of high pressure and temperature on their opto-electronic properties, including steady-state Photoluminescence emission properties, carrier lifetime evolution and Raman vibrations.

Research Skills

Raman, photoluminescence and absorption measurements: masterly operate two confocal Raman systems: Renishaw InVia and WITec alpha 300RAS Raman Microscopes

Dark field scattering measurement: precisely measure light scattered from single plasmonic nanoparticles with size < 10 nm.

High-pressure Technique: skillfully align and operate diamond anvil cell (DAC) to apply pressure up to 20~30 GPa.

Plasmonic nanostructure fabrication: write nanostructures by using Focused Ion Beam (FIB) setup.

Cathodoluminescence (CL) measurement: Being trained for Attolight Allalin 4027 Chronos time-resolve CL microscope. (Exchanged in University of Southampton, United Kingdom (Sep - Dec, 2015) for studying this technique.)