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.

Oxide-Assisted Growth of Semiconducting Nanowires

Abstract: In this contribution, we outline oxide-assisted growth (OAG) (distinct from the conventional metal-catalytic vapor-liquid-solid (VLS) process) for the growth of nanostructured materials. This synthesis technique, in whichoxides instead of metals play an important role in inducing the nucleation and growth of nanowires, is capable of producing large quantities of high-purity silicon nanowires with a preferential growth direction, uniform size, and long length, without the need for a metal catalyst. The OAG 1D nanomaterials synthesis is complementary to, and coexistent with, the conventional metal-catalyst VLS approach, and can be utilized to produce nanowires from a host of materials other than Si including Ge nanowires, carbon nanowires, silicon and SnO 2 nanoribbons, and Group III-V and II-VI compound semiconductor nanowires.

Patterned substrates of nano-graphene oxide mediating highly localized and efficient gene delivery.

Abstract: A facile approach was developed to fabricate patterned substrates of nano-graphene oxide, demonstrating highly localized and efficient gene delivery to multiple cell lines in a substrate-mediated manner. The GO substrates served as a valid platform to preconcentrate PEI/pDNA complexes and maintain their gradual releasing for a relatively long period of time. Our approach allowed successful gene delivery in selected groups of cells on the stripe-patterned GO substrates, without transfecting their neighbor cells directly cultured on glass. These GO substrates exhibited excellent biocompatibility and enabled effective gene transfection for various cell lines including stem cells, thus promising important applications in stem cell research and tissue engineering.

Surface Charge Transfer Doping via Transition Metal Oxides for Efficient p-Type Doping of II-VI Nanostructures.

Abstract: Wide band gap II–VI nanostructures are important building blocks for new-generation electronic and optoelectronic devices However, the difficulty of realizing p-type conductivity in these materials via conventional doping methods has severely handicapped the fabrication of p–n homojunctions and complementary circuits, which are the fundamental components for high-performance devices Herein, by using first-principles density functional theory calculations, we demonstrated a simple yet efficient way to achieve controlled p-type doping on II–VI nanostructures via surface charge transfer doping (SCTD) using high work function transition metal oxides such as MoO3, WO3, CrO3, and V2O5 as dopants Our calculations revealed that these oxides were capable of drawing electrons from II–VI nanostructures, leading to accumulation of positive charges (holes injection) in the II–VI nanostructures As a result, Fermi levels of the II–VI nanostructures were shifted toward the valence band regions after surface modificat

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