Zhiyuan Zeng

Bio: Zhiyuan Zeng is an academic researcher from City University of Hong Kong. The author has contributed to research in topics: Graphene & Anode. The author has an hindex of 48, co-authored 88 publications receiving 14285 citations. Previous affiliations of Zhiyuan Zeng include Nanyang Technological University & Lawrence Berkeley National Laboratory.

Metal dichalcogenide nanosheets: preparation, properties and applications

Abstract: Two-dimensional (2D) nanomaterials have received much attention in recent years, because of their unusual properties associated with their ultra-thin thickness and 2D morphology. Besides graphene which has aroused tremendous research interest, other types of 2D nanomaterials such as metal dichalcogenides have also been studied and applied in various applications including electronics, optoelectronics, energy storage devices, and so on. In this tutorial review, we will take MoS2 as a typical example to introduce the latest research development of 2D inorganic nanomaterials with emphasis on their preparation methods, properties and applications.

Single‐Layer Semiconducting Nanosheets: High‐Yield Preparation and Device Fabrication

Abstract: The common featureof these materials is that the bulk material forms are layeredstructures with strong covalent bonding in each layer andweak van der Waals forces between the layers. Therefore,single or few-layer nanosheets of these materials can beobtained by using adhesive tapes for mechanical cleavage.

Synthesis of Few-Layer MoS2 Nanosheet-Coated TiO2 Nanobelt Heterostructures for Enhanced Photocatalytic Activities

Abstract: MoS(2) nanosheet-coated TiO(2) nanobelt heterostructures--referred to as TiO(2)@MoS(2)--with a 3D hierarchical configuration are prepared via a hydrothermal reaction. The TiO(2) nanobelts used as a synthetic template inhibit the growth of MoS(2) crystals along the c-axis, resulting in a few-layer MoS(2) nanosheet coating on the TiO(2) nanobelts. The as-prepared TiO(2)@MoS(2) heterostructure shows a high photocatalytic hydrogen production even without the Pt co-catalyst. Importantly, the TiO(2)@MoS(2) heterostructure with 50 wt% of MoS(2) exhibits the highest hydrogen production rate of 1.6 mmol h(-1) g(-1). Moreover, such a heterostructure possesses a strong adsorption ability towards organic dyes and shows high performance in photocatalytic degradation of the dye molecules.

Single-Layer MoS2-Based Nanoprobes for Homogeneous Detection of Biomolecules

Abstract: A single-layer MoS2 nanosheet exhibits high fluorescence quenching ability and different affinity toward ssDNA versus dsDNA. As a proof of concept, the MoS2 nanosheet has been successfully used as a sensing platform for the detection of DNA and small molecules.

Fabrication of flexible MoS2 thin-film transistor arrays for practical gas-sensing applications.

Abstract: By combining two kinds of solution-processable two-dimensional materials, a flexible transistor array is fabricated in which MoS2 thin film is used as the active channel and reduced graphene oxide (rGO) film is used as the drain and source electrodes. The simple device configuration and the 1.5 mm-long MoS2 channel ensure highly reproducible device fabrication and operation. This flexible transistor array can be used as a highly sensitive gas sensor with excellent reproducibility. Compared to using rGO thin film as the active channel, this new gas sensor exhibits much higher sensitivity. Moreover, functionalization of the MoS2 thin film with Pt nanoparticles further increases the sensitivity by up to ∼3 times. The successful incorporation of a MoS2 thin-film into the electronic sensor promises its potential application in various electronic devices.

Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

Abstract: Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.

The chemistry of two-dimensional layered transition metal dichalcogenide nanosheets

Abstract: Ultrathin two-dimensional nanosheets of layered transition metal dichalcogenides (TMDs) are fundamentally and technologically intriguing. In contrast to the graphene sheet, they are chemically versatile. Mono- or few-layered TMDs - obtained either through exfoliation of bulk materials or bottom-up syntheses - are direct-gap semiconductors whose bandgap energy, as well as carrier type (n- or p-type), varies between compounds depending on their composition, structure and dimensionality. In this Review, we describe how the tunable electronic structure of TMDs makes them attractive for a variety of applications. They have been investigated as chemically active electrocatalysts for hydrogen evolution and hydrosulfurization, as well as electrically active materials in opto-electronics. Their morphologies and properties are also useful for energy storage applications such as electrodes for Li-ion batteries and supercapacitors.

Reviving the lithium metal anode for high-energy batteries

Abstract: Lithium-ion batteries have had a profound impact on our daily life, but inherent limitations make it difficult for Li-ion chemistries to meet the growing demands for portable electronics, electric vehicles and grid-scale energy storage. Therefore, chemistries beyond Li-ion are currently being investigated and need to be made viable for commercial applications. The use of metallic Li is one of the most favoured choices for next-generation Li batteries, especially Li-S and Li-air systems. After falling into oblivion for several decades because of safety concerns, metallic Li is now ready for a revival, thanks to the development of investigative tools and nanotechnology-based solutions. In this Review, we first summarize the current understanding on Li anodes, then highlight the recent key progress in materials design and advanced characterization techniques, and finally discuss the opportunities and possible directions for future development of Li anodes in applications.