光伏及纳米材料中的载流子动力学

发布日期:2018-10-17

报告人:文小明

       Center for Micro-Photonics

Swinburne University of Technology, Melbourne, Australia斯文本科技大学,墨尔本)

报告时间:10月17日 14:00

报告地点:光电所报告厅

报告摘要

超快时间分辨光谱及显微技术已经成为一类有效的先进技术,广泛用于光伏,光催化及发光材料及器件的光物理和载流子动力学研究。不仅能够提高对材料与相关器件中载流子运动的理解,并为设计和改进材料合成,器件设计及改进提供依据。本报告中我将简要介绍几种常用的时间分辨光谱技术,并报告超快时间分辨显微光谱技术应用于几种新材料(1)卤化物钙钛矿 (Perovskites),(2)InGaN/GaN多层量子阱纳米柱 (nanorods),(3) 碳纳米点/石墨烯量子点 (Carbon nanodots and graphene QDs) (4)金纳米团 (Au nanoclusters),研究其中载流子和移动离子的动力学过程,覆盖时间尺度从飞秒,皮秒直到稳态。在皮秒范围内,超快瞬态吸收证实了卤化物钙钛矿中热载流子的缓慢冷却,表明卤化物钙钛矿可能是有前途的下一代高效热载流子太阳能电池材料,其效率可超过Shockley-Queisser极限。使用高灵敏皮秒时间分辨光谱和显微技术,可以研究电子-空隙重组动力学,电子转移动力学,以及荧光淬灭过程。此外,钙钛矿材料中流动离子对载体动力学有显著的影响。移动离子迁移和积累导致以毫秒到数小时的超慢过程,这与I-V测量和光浸泡效应中的特性滞后密切相关。上述多时段时间分辨光谱技术及显微光谱技术,为材料相关的光物理过程研究提供了强大的工具。

报告人简介:

文小明博士,学士及硕士毕业于浙江大学光仪系。1989-2003在云南大学物理系任教,历任教授,副系主任。2007年在澳大利亚Swinburne University of Technology 获博士学位。后在澳大利亚墨尔本大学从事有机光伏材料的光物理研究,在台湾中央研究院从事纳米颗粒(半导体量子点,石墨烯量子点及金量子点)的光物理研究。2012-2016在世界著名的光伏学院Australian Centre for Advanced Photovoltaics, University of New South Wales (新南威尔士大学)从事太阳能材料与器件研究。与光伏之父马丁.格林教授合作进行钙钛矿太阳电池的研究,同时与多个研究组合作进行热载流子(hot carrier solar cells),CZTS 及量子点太阳电池等方向研究,担任高级研究员领导光物理方向研究。目前在澳大利亚斯文本科技大学Swinburne University of Technology从事新材料光物理的研究。曾在悉尼大学(University of Sydney, Australia)和大阪电器通信大学(Osaka Electrocommunication University, Japan)从事合作研究。专业特长为超快/时间分辨光谱,单分子光谱,光伏/光催化材料的光学及显微表征,纳米材料中的电子/激子/声子动力学(碳纳米点/石墨稀量子点graphene QDs,金属量子点metallic nanoclusters, 半导体量子点等)。在澳大利亚和台湾分别组建多种先进超快光谱学实验。出版超快光谱学专著一部(独立作者),在国际知名的高影响因子刊物发表SCI论文一百三十篇,其中包括5篇ESI高引用论文(top 1%)和一篇热点论文(top 0.1%),如:Nature Communications, Nano Letters, Advanced Energy Materials, Advanced Materials, Journal of Physical Chemistry Letters等。担任Scientific Reports(Nature子刊)等学术杂志编辑,同时担任三十多个国际著名学术期刊的审稿人(Nature Communications,Advanced Materials, ACS Nano, Advanced Energy Materials, Nanoscale etc.),担任澳洲国家科学基金(Australia Research Council-ARC)基金评审人。

 近期发表的学术论文:                        

1. J.F. Yang, X M Wen#, H.Z. Xia, R Sheng, Q Ma, J Kim, P Tapping, T Harada, T Kee, F Huang, T-B Cheng, M Green, AH Baillie, S Huang, S Shrestha, R Patterson and G Conibeer, Acoustic-optical phonon up-conversion and hot-phonon bottleneck in lead-halide perovskites, Nature Communications 8, 14120 (2017) (IF 12.124)  (Highly cited paper)

2. B. Wenger, P. Nayak, X M Wen, S. Kesava, N. Noel, and Henry Snaith, Consolidation of the optoelectronic properties of CH3NH3PbBr3 perovskite single crystals, Nature Communications 8, 590 (2017) (IF 12.124)

3. X, Deng, X. M. Wen#, JH Zheng, T Young, J Lau, J Kim, M Green, S Huang, AH Baillie, Dynamic study of the light soaking effect on perovskite solar cells by in-situ photoluminescence microscopy, Nano Energy, 46, 356 (2018)

4. WJ Chen; X M Wen#, JF Yang, M. Latzel, R Patterson, S Huang, S Shrestha, BH Jia, D Moss, S Christiansen and G Conibeer, Free charges versus excitons: photoluminescence investigation of InGaN/GaN multiple quantum well nanorods to their planar counterpart,Nanoscale, 10, 5358 (2018)

5. S. Chen, X. M. Wen#, JS Yun, S. Huang, M. Green, N.J. Jeon, W.S. Yang, J.H. Noh, J. Seo, S.I. Seok, A. Ho-Baillie, Spatial Distribution of Lead iodide and Local Passivation on Organo-Lead Halide Perovskite, ACS applied Materials and Interfaces, 9,6072 ( 2017) (IF 7.504)  

6. WJ Chen; X M Wen#, M. Latzel, M Heilmann, JF Yang, X Dai, S Huang, S Shrestha, R Patterson, SH Christiansen and G Conibeer, Nanoscale characterization of carrier dynamic and surface passivation in InGaN/GaN multiple quantum wells on GaN nanorods, ACS Applied Materials & Interfaces, 8, 31887 (2016), (IF 7.504)

7. Q. Ma, S. Huang, X. M. Wen, M. Green, A. Ho-Baillie, Hole Transport Layer Free Inorganic CsPbIBr 2 Perovskite Solar Cell by Dual Source Thermal Evaporation, Advanced Energy Materials, 6 (2016)1502202   (IF 16.721)  (Highly cited paper)

8. ZL Zhang, ZH Chen, L Yuan, WJ Chen, JF Yang, X M Wen, JB Zhang, L Hu, JA. Stride, GJ. Conibeer, RJ. Patterson, and SJ Huang, A New Passivation Route Leading to over 8% Efficient PbSe Quantum Dot Solar Cells via Direct Ion Exchange with Perovskite Nanocrystals, Advanced Materials, 29(2017) 1703214

9. X. M. Wen#, Y. Feng,  A. Ho-Baillie, S. Huang, F. Huang, Y-B. Cheng, and M Green, Defect Trapping States and Charge Carrier Recombination in Organic-Inorganic Halide Perovskites, Journal of Materials Chemistry C  2016, 4, 793-800    (IF5.256) (Highly cited paper)

10. X. M. Wen#; A. Ho-Baillie; S. Huang; R. Sheng; S. Chen; H.-c. Ko; M. A. Green, Mobile Charge-Induced Fluorescence Intermittency in Methylammonium Lead Bromide Perovskite, Nano letters 15, 4644 (2015).   (IF 12.712)