Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially in the fields of condensed matter physics, material science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, and optical properties, as well as their various potential applications, in this Review, we summarize the state-of-art progress on the ultrathin 2D nanomaterials with a particular emphasis on their recent advances. First, we introduce the unique advances on ultrathin 2D nanomaterials, followed by the description of their composition and crystal structures. The assortments of their synthetic methods are then summarized, including insights on their advantages and limitations, alongside some recommendations on suitable characterization techniques. We also discuss in detail the utilization of these ultrathin 2D nanomaterials for wide ranges of potential applications among the electronics/optoelectronics, electrocat...

Recent Advances in Ultrathin Two-Dimensional Nanomaterials

https://pr.ibs.re.kr/bitstream/8788114/3718/1/Recent%20development_Materials%20Today_Young%20Hee%20Lee.pdf

Recent Development of Two-Dimensional Transition Metal Dichalcogenides and Their Applications

As a two-dimensional (2D) material, molybdenum disulfide (MoS2) exhibits unique electronic and optical properties useful for a variety of optoelectronic applications including light harvesting. In this article, we review recent progress in the synthesis, properties and applications of MoS2 and related heterostructures. Heterostructured materials are developed to add more functionality or flexibility compared to single component materials. Our focus is on their novel properties and functionalities as well as emerging applications, especially in the areas of light energy harvesting or conversion. We highlight the correlation between structural properties and other properties including electronic, optical, and dynamic. Whenever appropriate, we also try to provide fundamental insight gained from experimental as well as theoretical studies. Finally, we discuss some current challenges and opportunities in technological applications of MoS2.

Synthesis, properties, and optoelectronic applications of two-dimensional MoS2 and MoS2-based heterostructures.

During recent decades, a giant leap in the development of nanotechnology has been witnessed. Numerous nanomaterials with different dimensions and unprecedented features have been developed and provided unimaginably wide scope to solve the challenging problems in biomedicine, such as cancer diagnosis and therapy. Recently, two-dimensional (2D) transition metal dichalcogenide (TMDC) nanosheets (NSs), including MoS2 , WS2 , and etc., have emerged as novel inorganic graphene analogues and attracted tremendous attention due to their unique structures and distinctive properties, and opened up great opportunities for biomedical applications, including ultrasensitive biosensing, biological imaging, drug delivery, cancer therapy, and antibacterial treatment. A comprehensive overview of different synthetic methods of ultrathin 2D TMDC NSs and their state-of-the-art biomedical applications, especially those that have appeared in the past few years, is presented. At the end of this review, the future opportunities and challenges for 2D TMDC NSs in biomedicine are also discussed.

Recent Advances in Synthesis and Biomedical Applications of Two-Dimensional Transition Metal Dichalcogenide Nanosheets.

Molybdenum disulfide (MoS2 ), a typical layered 2D transition metal dichalcogenide, has received colossal interest in the past few years due to its unique structural, physicochemical, optical, and biological properties. While MoS2 is mostly applied in traditional industries such as dry lubricants, intercalation agents, and negative electrode material in lithium-ion batteries, its 2D and 0D forms have led to diverse applications in sensing, catalysis, therapy, and imaging. Herein, a systematic overview of the progress that is made in the field of MoS2 research with an emphasis on its different biomedical applications is presented. This article provides a general discussion on the basic structure and property of MoS2 and gives a detailed description of its different morphologies that are synthesized so far, namely, nanosheets, nanotubes, and quantum dots along with synthesis strategies. The biomedical applications of MoS2 -based nanocomposites are also described in detail and categorically, such as in varied therapeutic and diagnostic modalities like drug delivery, gene delivery, phototherapy, combined therapy, bioimaging, theranostics, and biosensing. Finally, a brief commentary on the current challenges and limitations being faced is provided, along with a discussion of some future perspectives for the overall improvement of MoS2 -based nanocomposites as a potential nanomedicine.

2D MoS2 -Based Nanomaterials for Therapeutic, Bioimaging, and Biosensing Applications.

Prostate specific antigen (PSA) is a significant and the most widely used biomarker for the early diagnosis of prostate cancer and its subsequent treatment. A MoS2 nanosheet is a two-dimensional (2D) layered nanomaterial analogous to graphene. However, a MoS2 nanosheet has a higher fluorescence-quenching ability than graphene when applied to a dye-labeled single-stranded DNA probe. In this work, we propose a novel aptamer-functionalized MoS2 nanosheet fluorescent biosensor that detects PSA. The binding of the aptamer to the target PSA induces a rigid aptamer structure which makes the integration with the MoS2 nanosheet very weak. This results in the release of the aptamer probe from the nanosheet surface and restores the quenched fluorescence. This approach has the advantage of simple design and rapid detection of PSA. The biosensor has the merits of high sensitivity and high selectivity with a detection limit for the PSA of 0.2 ng/mL. The biosensor was also successfully applied to the detection of PSA in human serum samples with satisfactory results. The foregoing indicates its promising application to real-life biological samples.

A novel aptamer-functionalized MoS2 nanosheet fluorescent biosensor for sensitive detection of prostate specific antigen.

Signal amplification strategy for sensitive immunoassay of prostate specific antigen (PSA) based on ferrocene incorporated polystyrene spheres.

The invention provides a preparation method of a polystyrene-coated ferrocene microsphere. The preparation method comprises the following steps of: dispersing polyvinyl pyrrolidone in mixed liquor of alcohol and water to obtain a dispersion system, wherein the volume ratio of the alcohol to the water is (15:1) to (20:1); and introducing nitrogen gas or inert gas to the dispersion system, heating up to 70 DEG C-75 DEG C, adding azodiisobutyronitrile and styrene, adding the ferrocene after 60-150 seconds to react for 12-24 hours, cooling, centrifuging and washing to obtain the polystyrene-coated ferrocene microsphere, wherein the volume ratio of the dispersion system to the styrene is (4:1)-(6:1), the mass ratio of the polyvinyl pyrrolidone to the styrene is 0.1-0.15, the mass ratio of the azodiisobutyronitrile to the styrene is 0.008-0.012, and the mass ratio of the ferrocene to the styrene is 0.00024-0.00071. The invention provides an electrochemical immunosensor. The electrochemical immunosensor comprises a working electrode, wherein the polystyrene-coated ferrocene microsphere, which is obtained by the preparation method of the polystyrene-coated ferrocene microsphere, is modified on the working electrode.

Lu Ding

Papers

A novel aptamer-functionalized MoS2 nanosheet fluorescent biosensor for sensitive detection of prostate specific antigen.

Signal amplification strategy for sensitive immunoassay of prostate specific antigen (PSA) based on ferrocene incorporated polystyrene spheres.

Preparation method of polystyrene-coated ferrocene microsphere and application of microsphere