Shuit-Tong Lee

Bio: Shuit-Tong Lee is an academic researcher from Soochow University (Suzhou). The author has contributed to research in topics: Silicon & Nanowire. The author has an hindex of 138, co-authored 1121 publications receiving 77112 citations. Previous affiliations of Shuit-Tong Lee include University of British Columbia & Hong Kong University of Science and Technology.

Photoelectron spectra of OCSe, SCSe, and CSe2

Abstract: The HeI photoelectron spectra of OCSe, SCSe, and CSe2 have been measured and the electronic states associated with the various observed ionization potentials have been assigned. Comparison of the measured Franck‐Condon transition probabilities with those calculated theoretically enables us to determine the geometries of the molecular ions studied.

Non-doped-type white organic light-emitting devices based on yellow-emitting ultrathin 5,6,11,12-tetraphenylnaphthacene and blue-emitting 4,4′-bis(2,2′-diphenyl vinyl)-1,1′-biphenyl

Abstract: Non-doped-type white organic light-emitting devices based on the ultrathin yellow-emitting layer (0.1 nm) of 5,6,11,12-tetraphenylnaphthacene (rubrene) and the thick blue-emitting layer of 4,4'-bis(2,2'-diphenyl vinyl)-1,1'-biphenyl (DPVBi) made from vacuum-deposited organic thin films are reported. The recombination zone of the devices can be adjusted by changing the thicknesses of DPVBi and the electron transport layers (tris-(8-hydroxyquinoline)aluminium, Alq3). In the device with 30 nm DPVBi and 30 nm Alq3, bright white light, over 10 000 cd m−2, was successfully obtained at a low drive voltage of ~10 V. The highest power efficiency is 3.18 lm W−1 at 4 V, and stable 1931 Commision International de L'Eclairage coordinates are obtained for luminance ranging from 100 to 20 000 cd m−2 (at ~12 V).

Mechanism of non-metal catalytic growth of graphene on silicon

Abstract: Compared to preparation on metal substrates, graphene synthesis on non-metal surfaces is highly desirable to avoid the deleterious metallic effects in fabrication of electronic devices. However, study of graphene growth mechanism on non-metal surfaces is rare and little understood. Here, we report that few-layers graphene films can be grown directly on silicon-on-insulator surface. Furthermore, the graphene growth mechanism on non-metal surfaces is proposed as a surface reaction, adsorption, decomposition, and accumulation process.

Silicon Nanowires for Photovoltaic Solar Energy Conversion

Abstract: Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon nanowires (SiNWs) are under active investigation for PV applications because they offer novel approaches for solar-to-electric energy conversion leading to high-efficiency devices via simple manufacturing. This article reviews the recent developments in the utilization of SiNWs for PV applications, the relationship between SiNW-based PV device structure and performance, and the challenges to obtaining high-performance cost-effective solar cells.

A roadmap for graphene

Abstract: Recent years have witnessed many breakthroughs in research on graphene (the first two-dimensional atomic crystal) as well as a significant advance in the mass production of this material. This one-atom-thick fabric of carbon uniquely combines extreme mechanical strength, exceptionally high electronic and thermal conductivities, impermeability to gases, as well as many other supreme properties, all of which make it highly attractive for numerous applications. Here we review recent progress in graphene research and in the development of production methods, and critically analyse the feasibility of various graphene applications.

High-performance lithium battery anodes using silicon nanowires

Abstract: There is great interest in developing rechargeable lithium batteries with higher energy capacity and longer cycle life for applications in portable electronic devices, electric vehicles and implantable medical devices. Silicon is an attractive anode material for lithium batteries because it has a low discharge potential and the highest known theoretical charge capacity (4,200 mAh g(-1); ref. 2). Although this is more than ten times higher than existing graphite anodes and much larger than various nitride and oxide materials, silicon anodes have limited applications because silicon's volume changes by 400% upon insertion and extraction of lithium which results in pulverization and capacity fading. Here, we show that silicon nanowire battery electrodes circumvent these issues as they can accommodate large strain without pulverization, provide good electronic contact and conduction, and display short lithium insertion distances. We achieved the theoretical charge capacity for silicon anodes and maintained a discharge capacity close to 75% of this maximum, with little fading during cycling.

Nanobelts of Semiconducting Oxides

Abstract: Ultralong beltlike (or ribbonlike) nanostructures (so-called nanobelts) were successfully synthesized for semiconducting oxides of zinc, tin, indium, cadmium, and gallium by simply evaporating the desired commercial metal oxide powders at high temperatures. The as-synthesized oxide nanobelts are pure, structurally uniform, and single crystalline, and most of them are free from defects and dislocations. They have a rectanglelike cross section with typical widths of 30 to 300 nanometers, width-to-thickness ratios of 5 to 10, and lengths of up to a few millimeters. The beltlike morphology appears to be a distinctive and common structural characteristic for the family of semiconducting oxides with cations of different valence states and materials of distinct crystallographic structures. The nanobelts could be an ideal system for fully understanding dimensionally confined transport phenomena in functional oxides and building functional devices along individual nanobelts.

Raman spectroscopy as a versatile tool for studying the properties of graphene

Abstract: Raman spectroscopy is an integral part of graphene research. It is used to determine the number and orientation of layers, the quality and types of edge, and the effects of perturbations, such as electric and magnetic fields, strain, doping, disorder and functional groups. This, in turn, provides insight into all sp(2)-bonded carbon allotropes, because graphene is their fundamental building block. Here we review the state of the art, future directions and open questions in Raman spectroscopy of graphene. We describe essential physical processes whose importance has only recently been recognized, such as the various types of resonance at play, and the role of quantum interference. We update all basic concepts and notations, and propose a terminology that is able to describe any result in literature. We finally highlight the potential of Raman spectroscopy for layered materials other than graphene.

Aggregation-Induced Emission: Together We Shine, United We Soar!

Abstract: Ju Mei,†,‡,∥ Nelson L. C. Leung,†,‡,∥ Ryan T. K. Kwok,†,‡ Jacky W. Y. Lam,†,‡ and Ben Zhong Tang*,†,‡,§ †HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China ‡Department of Chemistry, HKUST Jockey Club Institute for Advanced Study, Institute of Molecular Functional Materials, Division of Biomedical Engineering, State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China Guangdong Innovative Research Team, SCUT-HKUST Joint Research Laboratory, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China