时间：2015年7月15日18:30
地点：教十一三楼分析测试中心会议室318房间
报告题目、内容和报告人简历如下
Development of Some Novel Two-dimensional Crystals and their Heterostructures
LIU Zheng
1 School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
Technological University, 639798, Singapore
1 School of Materials Science and Engineering, Nanyang Technological University, 639798, Singapore
Technological University, 639798, Singapore
Abstract:
The one-atom-think layer e.g. graphene has fantastic properties and attracted tremendous interests in these years, which opens a window for various two-dimensional (2D) materials. However, making large-size and high-quality 2D is still a great challenge. Using chemical vapour deposition, we have successfully synthesized a wide varieties of 2D materials with high quality and large scale via chemical vapor deposition (CVD) method, including hexagonal boron nitrides (h-BN), transition metal dichalcogenides e.g. molybdenum disulphides (MoS2), tungsten disulphides (WS2), cadmium sulphides (CdS), gallium selenides (GaSe) and molybdenum selenides (MoSe2) belonging to binary 2D layers. Ternary 2D layers including BCN, MoS2xSe2(1-x), are also successfully prepared. In addition, fabrication of 2D heterostructuresincluding vertical and lateral graphene/h-BN, vertical and lateral TMDs are also demonstrated. Tehre work provide a better understanding of the understanding of the atomic layered materials in terms of the synthesis, atomic structure, alloying and mechanical properties. Complementary to the 2D atomic layered grown by CVD method, 2D single-crystal bulk are also prepared via solid reaction including WTe2, SnSe2, PtS2, PtSe2, PdSe2, Res2, WSe2xTe2(1-x), Ta2NiS5 and Ta2NiSe5 whose properties are now under exploration. Applications of the 2D layers including optoelectronic devices, energy device and smart coating have also been demonstrated.
[1]. Zheng Liu, Matin Amani, Sina Najmaei, etc. Strain and Structure Heterogeneity in MoS2 Atomic Layers Grown by Chemical Vapor Deposition. Nature Communications 2014, 5, 5246
[2]. Yongji Gong, Junhao Lin, Xingli Wang, Gang Shi, Sidong Lei, Zhong Lin, Xiaolong Zou, Gonglan Ye, Robert Vajtai, Boris I. Yakobson, Humberto Terrones, Mauricio Terrones, Beng Kang Tay, Jun Lou, Sokrates T. Pantelides, Zheng Liu, Wu Zhou, Pulickel M. Ajayan Vertical and In-Plane Heterostructures from WS2/MoS2 Monolayers. Nature Materials 2014, 13, 1135
[3]. Peng Zhang, Lulu Ma, Feifei Fan, Zhi Zeng, Cheng Peng, Phillip Loya, Zheng Liu, Yongji Gong, Jiangnan Zhang, Xing-xiang Zhang, Pulickel Ajayan, Ting Zhu, and Jun Lou. Fracture Toughness of Graphene. Nature Communications 2014, 5, 3782
[4]. Y. Gong, G. Shi, Z. Zhang, W. Zhou, J. Jung, W. Gao, L. Ma, Y. Yang, S. Yang, G. You, R. Vajtai, Q. Xu, A. MacDonald, B. I. Yakobson, J. Lou, Z. Liu*, and P.M. Ajayan Direct Chemical Conversion of Graphene to Boron, Nitrogen and Carbon Containing Atomic Layers. Nature Communications, 2014, 5, 319
Biography
Dr. Zheng Liu received his B.S. degrees (2005) at Nankai University (China), and completed his Ph.D at National Center for Nanoscience and Technology (NCNST, China), working on the synthesis and energy harvest of carbon nanotubes. He then worked in Prof. Pulickel M. Ajayan and Prof. Jun Lou’s groups as a joint postdoc research fellow (2010~2012) and research scientist (2012~2013) at Rice University (USA), focusing on the synthesis and applications of two-dimensional (2D) crystals, including graphene, hexagonal boron nitride, oxides and transition metal dichalcogenides (TMD: MoS2, MoSe2 etc). He has made contributions not only the synthesis of 2D heterostructures such as vertical and lateral graphene/h-BN, but also the 2D materials based nanoelectronics, active nano-systems and high performance energy components, e.g. resonators, graphene photodetectors.
He has published more than 60 peer-reviewed papers in top journals including 9 papers in Nature serial journal (Nat Mater, Nat Nanotech and Nat Comm); 17 in Nano Lett; 7 in Adv Mater; 7 in ACS Nano, with total citations more than 3600 and h-index of 30. These works have also been reported by Science daily, IEEE spectrum, etc., and highlighted by the top journals such as Nature Physics, Nature Nanotechnology, Chem Int Ed, etc. He was also a recipient of the World Technology Award in Energy category in 2012. This award has been presented as a way to honor those in doing “the innovative work of the greatest likely long-term significance.” He was awarded the prestigious Singapore NRF Fellowship and Nanyang Assistant Professorship in 2013.
