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1.
Phuong Pham Thi Thuy Phuong Nguyen Nguyen Kumar P. Senthil Duy Nguyen Phuc Hoang Van Le Quyet Ngoc Le Thi Bao Jalil A. A. Rajendran Saravanan Cheng Chin Kui Nguyen Thanh-Huong Dinh Minh Tuan Nguyen Vo Dai-Viet N. 《Topics in Catalysis》2023,66(1-4):41-52
Topics in Catalysis - CO2 reforming of methanol for producing hydrogen was experimentally carried out in a fixed-bed reactor on 10%Ni/SiO2. The 10%Ni/SiO2 was completely reduced during H2... 相似文献
2.
Pham Van Quyet Bernice Mei Jin Tan Celine Valeria Liew Lai Wah Chan Quan Sing Ng 《Drug development and industrial pharmacy》2018,44(4):624-631
L-NG-nitroarginine (LNNA), an analog of L-arginine, is a competitive inhibitor of nitric oxide synthase which causes the selective reduction of blood flow to tumor cells. Despite the potential of LNNA to function as an adjuvant in cancer therapies, its poor solubility and stability have hindered the development of an injectable formulation of LNNA that is suitable for human administration. This work, for the first time, details a systematic study on the determination of equilibrium Ka constants and the rate law of LNNA degradation. The four Ka values of LNNA were determined to be 1.03, 1.10?×?10?2, 2.51?×?10?10, and 1.33?×?10?13 M. From the kinetic and equilibrium studies, we have shown that the deprotonated form of LNNA is the main form of LNNA that undergoes degradation in aqueous media at room temperature. The rate law of LNNA degradation was found to be first order with respect to OH? concentration and first order with respect to LNNA? concentration. The rate constant at 25?°C and 1?atm was determined to be 0.04453 M?1min?1. A base catalyzed mechanism of LNNA degradation was proposed based on the kinetic study. The mechanism was found to be very useful in explaining the discrepancies and changes of the rate law at different pH values. It is thus recommended that LNNA should be formulated as a concentrated solution in acidic conditions for maximum chemical stability during storage and be diluted with a basic solution to near physiological pH just before administration. 相似文献
3.
Van-Huy Nguyen Thang P Nguyen Thu-Ha Le Dai-Viet N Vo Dang LT Nguyen Quang Thang Trinh Il Tae Kim Quyet Van Le 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(10):2597-2607
Hydrogen gas has been attracting significant interest as an emerging energy source that is clean, sustainable, and renewable. Primarily, it can be produced via photoelectrochemical (PEC) splitting of water using solar energy. Among the various catalysts employed for the photoreduction of water, two-dimensional transition metal dichalcogenides (2D-TMDs) are inarguably the best candidates toward industrialization because they have extraordinary physical, optical, and electric properties, and are solution-processable at low costs. In this review, we focus on the development of 2D-TMDs and their PEC properties toward the hydrogen evolution reaction. First, the synthesis and properties of 2D materials are summarized and discussed. Next, the strategies for improving the photocatalytic activity of the 2D material-based catalysts for water splitting are thoroughly investigated. Finally, the remaining challenges and direction for the future development of 2D-TMDs in PEC catalysis-derived hydrogen evolution reaction are addressed. © 2020 Society of Chemical Industry 相似文献
4.
Gia Quyet Ngo Antony George Robin Tristan Klaus Schock Alessandro Tuniz Emad Najafidehaghani Ziyang Gan Nils C. Geib Tobias Bucher Heiko Knopf Sina Saravi Christof Neumann Tilman Lühder Erik P. Schartner Stephen C. Warren-Smith Heike Ebendorff-Heidepriem Thomas Pertsch Markus A. Schmidt Andrey Turchanin Falk Eilenberger 《Advanced materials (Deerfield Beach, Fla.)》2020,32(47):2003826
Atomically thin transition metal dichalcogenides are highly promising for integrated optoelectronic and photonic systems due to their exciton-driven linear and nonlinear interactions with light. Integrating them into optical fibers yields novel opportunities in optical communication, remote sensing, and all-fiber optoelectronics. However, the scalable and reproducible deposition of high-quality monolayers on optical fibers is a challenge. Here, the chemical vapor deposition of monolayer MoS2 and WS2 crystals on the core of microstructured exposed-core optical fibers and their interaction with the fibers’ guided modes are reported. Two distinct application possibilities of 2D-functionalized waveguides to exemplify their potential are demonstrated. First, the excitonic 2D material photoluminescence is simultaneously excited and collected with the fiber modes, opening a novel route to remote sensing. Then it is shown that third-harmonic generation is modified by the highly localized nonlinear polarization of the monolayers, yielding a new avenue to tailor nonlinear optical processes in fibers. It is anticipated that the results may lead to significant advances in optical-fiber-based technologies. 相似文献
5.
Van-Huy Nguyen Seyed Ali Delbari Mehdi Shahedi Asl Quyet Van Le Abbas Sabahi Namini Zohre Ahmadi Mohammad Farvizi Mohsen Mohammadi Mohammadreza Shokouhimehr 《Ceramics International》2021,47(9):12459-12466
This research explores the sintering behavior and microstructure of ZrB2-based materials containing graphene nano-platelets (GNPs) and SiC whiskers (SiCw). Spark plasma sintering (SPS) process at 1900 °C was implemented to sinter the specimen, leading to a composite with 100% relative density. High-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), field emission-electron probe microanalyzer (FE-EPMA), and high-resolution X-ray diffractometry (HRXRD) were employed to study the SPSed sample, along with the thermodynamics predictions. According to the HRXRD result and microstructural observations, the sintering process was non-reactive, which was endorsed with the XPS analysis. Furthermore, graphene presented a beneficial role for eradicating the oxide impurities in the sample during the sintering. Such oxide impurities were reduced to the original phases of SiC and ZrB2, contributing to porosity removal. Nanostructural investigations revealed the formation of ultrathin amorphous interfaces (~10 nm) between ZrB2/graphene phases, disordered atomic planes in graphene platelets, and dislocations in ZrB2 grains. One reason for generating crystalline defects in the microstructure was found out to be the mismatches amongst the elastic properties of the available compounds in the system. 相似文献
6.
Air‐Stable Cesium Lead Iodide Perovskite for Ultra‐Low Operating Voltage Resistive Switching 下载免费PDF全文
Ji Su Han Quyet Van Le Jaeho Choi Kootak Hong Cheon Woo Moon Taemin Ludvic Kim Hyojung Kim Soo Young Kim Ho Won Jang 《Advanced functional materials》2018,28(5)
CsPbX3 (X = halide, Cl, Br, or I) all‐inorganic halide perovskites (IHPs) are regarded as promising functional materials because of their tunable optoelectronic characteristics and superior stability to organic–inorganic hybrid halide perovskites. Herein, nonvolatile resistive switching (RS) memory devices based on all‐inorganic CsPbI3 perovskite are reported. An air‐stable CsPbI3 perovskite film with a thickness of only 200 nm is successfully synthesized on a platinum‐coated silicon substrate using low temperature all‐solution process. The RS memory devices of Ag/polymethylmethacrylate (PMMA)/CsPbI3/Pt/Ti/SiO2/Si structure exhibit reproducible and reliable bipolar switching characteristics with an ultralow operating voltage (<+0.2 V), high on/off ratio (>106), reversible RS by pulse voltage operation (pulse duration < 1 ms), and multilevel data storage. The mechanical flexibility of the CsPbI3 perovskite RS memory device on a flexible substrate is also successfully confirmed. With analyzing the influence of phase transition in CsPbI3 on RS characteristics, a mechanism involving conducting filaments formed by metal cation migration is proposed to explain the RS behavior of the memory device. This study will contribute to the understanding of the intrinsic characteristics of IHPs for low‐voltage resistive switching and demonstrate the huge potential of them for use in low‐power consumption nonvolatile memory devices on next‐generation computing systems. 相似文献
7.
Emad Najafidehaghani Ziyang Gan Antony George Tibor Lehnert Gia Quyet Ngo Christof Neumann Tobias Bucher Isabelle Staude David Kaiser Tobias Vogl Uwe Hübner Ute Kaiser Falk Eilenberger Andrey Turchanin 《Advanced functional materials》2021,31(27):2101086
Lateral heterostructures of dissimilar monolayer transition metal dichalcogenides provide great opportunities to build 1D in-plane p–n junctions for sub-nanometer thin low-power electronic, optoelectronic, optical, and sensing devices. Electronic and optoelectronic applications of such p–n junction devices fabricated using a scalable one-pot chemical vapor deposition process yielding MoSe2-WSe2 lateral heterostructures are reported here. The growth of the monolayer lateral heterostructures is achieved by in situ controlling the partial pressures of the oxide precursors by a two-step heating protocol. The grown lateral heterostructures are characterized structurally and optically using optical microscopy, Raman spectroscopy/microscopy, and photoluminescence spectroscopy/microscopy. High-resolution transmission electron microscopy further confirms the high-quality 1D boundary between MoSe2 and WSe2 in the lateral heterostructure. p–n junction devices are fabricated from these lateral heterostructures and their applicability as rectifiers, solar cells, self-powered photovoltaic photodetectors, ambipolar transistors, and electroluminescent light emitters are demonstrated. 相似文献
8.
Sun Gil Kim Quyet Van Le Ji Su Han Hyojung Kim Min‐Ju Choi Sol A Lee Taemin Ludvic Kim Sang Bum Kim Soo Young Kim Ho Won Jang 《Advanced functional materials》2019,29(49)
Neuromorphic computing, which mimics biological neural networks, can overcome the high‐power and large‐throughput problems of current von Neumann computing. Two‐terminal memristors are regarded as promising candidates for artificial synapses, which are the fundamental functional units of neuromorphic computing systems. All‐inorganic CsPbI3 perovskite‐based memristors are feasible to use in resistive switching memory and artificial synapses due to their fast ion migration. However, the ideal perovskite phase α‐CsPbI3 is structurally unstable at ambient temperature and rapidly degrades to a non‐perovskite δ‐CsPbI3 phase. Here, dual‐phase (Cs3Bi2I9)0.4?(CsPbI3)0.6 is successfully fabricated to achieve improved air stability and surface morphology compared to each single phase. Notably, the Ag/polymethylmethacrylate/(Cs3Bi2I9)0.4?(CsPbI3)0.6/Pt device exhibits non‐volatile memory functions with an endurance of ≈103 cycles and retention of ≈104 s with low operation voltages. Moreover, the device successfully emulates synaptic behavior such as long‐term potentiation/depression and spike timing/width‐dependent plasticity. This study will contribute to improving the structural and mechanical stability of all‐inorganic halide perovskites (IHPs) via the formation of dual phase. In addition, it proves the great potential of IHPs for use in low‐power non‐volatile memory devices and electronic synapses. 相似文献
9.
Serrano-Garcia William Jayathilaka Wanasinghe Arachchige Dumith Madushanka Chinnappan Amutha Tran Thang Quyet Baskar Chinnappan Thomas Sylvia Wilson Ramakrishna Seeram 《中国科学:技术科学(英文版)》2019,62(6):895-902
In the present review, we have selected advances in electrospinning nanofibers that we envision to be embedded in textiles and wearables. These nanofibers have been proven to be excellent options for applications such as power generation, sensing, and communication. Their similitude with already known woven meshes makes these fibers perfect for electronically active textiles.These fibers offer well known characteristics such as mechanical flexibility, high surface area-to-volume ratio, light weight and can be tuned by carefully selecting the active materials in the precursor solution. Here we will discuss polymers with electroactive, piezoelectric, triboelectric and their composites that have been used in fiber structures by using the electrospinning technique. 相似文献
10.
Performances of Liquid‐Exfoliated Transition Metal Dichalcogenides as Hole Injection Layers in Organic Light‐Emitting Diodes 下载免费PDF全文
Cheolmin Kim Thang Phan Nguyen Quyet Van Le Jong‐Myeong Jeon Ho Won Jang Soo Young Kim 《Advanced functional materials》2015,25(28):4512-4519
2D transition metal dichalcogenide (TMD) nanosheets, including MoS2, WS2, and TaS2, are used as hole injection layers (HILs) in organic light‐emitting diodes (OLEDs). MoS2, WS2, and TaS2 nanosheets are prepared using an exfoliation by ultrasonication method. The thicknesses and sizes of the TMD nanosheets are measured to be 3.1–4.3 nm and more than 100 nm, respectively. The work functions of the TMD nanosheets increase from 4.4–4.9 to 4.9–5.1 eV following ultraviolet/ozone (UVO) treatment. The turn‐on voltages at 10 cd m?2 for UVO‐treated TMD‐based devices decrease from 7.3–12.8 to 4.3–4.4 V and maximum luminance efficiencies increase from 5.74–9.04 to 12.01–12.66 cd A?1. In addition, this study confirms that the stabilities of the devices in air can be prolonged by using UVO‐treated TMDs as HILs in OLEDs. These results demonstrate the great potential of liquid‐exfoliated TMD nanosheets for use as HILs in OLEDs. 相似文献