Updated on 2024/04/01

写真a

 
ALOWASHEEIR Azhar
 
Organization
Graduate School of Engineering Materials Process Engineering 2 Assistant Professor
Graduate School
Graduate School of Engineering
Undergraduate School
School of Engineering Materials Science and Engineering
Title
Assistant Professor
Contact information
メールアドレス
External link

Degree 1

  1. 工学博士 ( 2019.2   早稲田大学 ) 

Research Areas 1

  1. Nanotechnology/Materials / Inorganic compounds and inorganic materials chemistry

 

Papers 6

  1. Synthesis of millimeter-scale ZIF-8 single crystals and their reversible crystal structure changes

    Alowasheeir, A; Torad, NL; Asahi, T; Alshehri, SM; Ahamad, T; Bando, Y; Eguchi, M; Yamauchi, Y; Terasawa, Y; Han, MS

    SCIENCE AND TECHNOLOGY OF ADVANCED MATERIALS   Vol. 25 ( 1 ) page: 2292485   2024.12

     More details

    Language:English   Publisher:Science and Technology of Advanced Materials  

    Among various metal-organic frameworks (MOFs), the zeolitic imidazole framework (ZIF), constructed by the regular arrangement of 2-methylimidazole and metal ions, has garnered significant attention due to its distinctive crystals and pore structures. Variations in the sizes and shapes of ZIF crystals have been reported by changing the synthesis parameters, such as the molar ratios of organic ligands to metal ions, choice of solvents, and temperatures. Nonetheless, the giant ZIF-8 single crystals beyond the typical range have rarely been reported. Herein, we present the synthesis of millimeter-scale single crystal ZIF-8 using the solvothermal method in N,N-diethylformamide. The resulting 1-mm single crystal is carefully characterized through N2 adsorption-desorption isotherms, scanning electron microscopy, and other analytical techniques. Additionally, single-crystal X-ray diffraction is employed to comprehensively investigate the framework’s mobility at various temperatures.

    DOI: 10.1080/14686996.2023.2292485

    Web of Science

    Scopus

    PubMed

  2. Enlarging the porosity of metal-organic framework-derived carbons for supercapacitor applications by a template-free ethylene glycol etching method

    azhar alowasheeir

    Journal of Materials Chemistry A   Vol. 11 ( 24 ) page: 12759 - 12769   2023.6

     More details

    Publishing type:Research paper (scientific journal)  

    DOI: 10.1039/d2ta06307g

    Web of Science

    researchmap

  3. Mesoporous Semiconductive Bi<sub>2</sub>Se<sub>3</sub> Films

    Nagaura, T; Ashok, A; Alowasheeir, A; Vasanth, A; Han, MS; Yamauchi, Y

    NANO LETTERS   Vol. 23 ( 12 ) page: 5424 - 5429   2023.6

     More details

    Language:English   Publisher:Nano Letters  

    Bi2Se3 is a semiconductive material possessing a bandgap of 0.3 eV, and its unique band structure has paved the way for diverse applications. Herein, we demonstrate a robust platform for synthesizing mesoporous Bi2Se3 films with uniform pore sizes via electrodeposition. Block copolymer micelles act as soft templates in the electrolyte to create a 3D porous nanoarchitecture. By controlling the length of the block copolymer, the pore size is adjusted to 9 and 17 nm precisely. The nonporous Bi2Se3 film exhibits a tunneling current in a vertical direction of 52.0 nA, but upon introducing porosity (9 nm pores), the tunneling current increases significantly to 684.6 nA, suggesting that the conductivity of Bi2Se3 films is dependent on the pore structure and surface area. The abundant porous architecture exposes a larger surface area of Bi2Se3 to the surrounding air within the same volume, thereby augmenting its metallic properties.

    DOI: 10.1021/acs.nanolett.3c00183

    Web of Science

    Scopus

    PubMed

  4. Intermetallic Compound TiM (M=Co, Fe) with a Layered Structure Prepared by Deoxidizing Ilmenite-type Oxides in Molten LiCl-CaH<sub>2</sub> Mixtures

    Kobayashi, Y; Nagaura, T; Alowasheeir, A; Tada, S; Yusuke, Y

    CHEMISTRY-A EUROPEAN JOURNAL   Vol. 29 ( 32 ) page: e202300194   2023.6

     More details

    Language:English   Publisher:Chemistry - A European Journal  

    CsCl-type intermetallic compounds TiM (M=Co, Fe) were obtained by deoxidizing trigonal ilmenite-type MTiO3 with a reducing agent CaH2 in molten LiCl at 600 °C. X-ray diffraction, nitrogen adsorption, scanning electron microscopy, and transmission electron microscopy with energy-dispersive X-ray, and X-ray photoelectron spectroscopy analyses revealed the formation of nanoscale layered structures, which enhanced specific surface areas (approximately 20 m2/g) in the intermetallic compounds. In the initial deoxidation stage, Li2TiO3-like compounds were observed as an intermediate, suggesting the substitution of M in MTiO3 by Li from the molten LiCl. Compound MTiO3 has a layered structure perpendicular to the c axis of the trigonal structure, suggesting that the layered structures may originate from the crystal structure of the precursors. Formation of the Li2TiO3-like intermediate may help maintain the original layered structure during deoxidation and the subsequent alloying at temperatures as low as 600 °C.

    DOI: 10.1002/chem.202300194

    Web of Science

    Scopus

    PubMed

  5. Particle size optimization of metal-organic frameworks for superior capacitive deionization in oxygenated saline water

    Xing, ZY; Xuan, XX; Hu, HY; Li, MH; Gao, HM; Alowasheeir, A; Jiang, D; Zhu, LY; Li, ZT; Kang, YQ; Zhang, J; Yi, XB; Yamauchi, Y; Xu, XT

    CHEMICAL COMMUNICATIONS   Vol. 59 ( 30 ) page: 4515 - 4518   2023.4

     More details

    Language:English   Publisher:Chemical Communications  

    Pyrolysis-free metal-organic frameworks (MOFs) with optimized particle sizes were used as capacitive deionization (CDI) materials in oxygenated saline water. Upon decreasing the particle size of the MOFs, excellent cycling stability and higher CDI performance were achieved. This was possibly due to the improvement in charge transfer and electrolyte permeation, uncovering the significance of particle size control in improving CDI performance.

    DOI: 10.1039/d2cc06460j

    Web of Science

    Scopus

    PubMed

  6. Extraordinary Acceleration of an Electrophilic Reaction Driven by the Polar Surface of 2D Aluminosilicate Nanosheets. International journal

    Nagy L Torad, Yuta Tsuji, Azhar Alowasheeir, Masako Momotake, Kazuki Okazawa, Kazunari Yoshizawa, Michio Matsumoto, Masafumi Yamato, Yusuke Yamauchi, Miharu Eguchi

    Small (Weinheim an der Bergstrasse, Germany)   Vol. 19 ( 11 ) page: e2205857   2023.3

     More details

    Language:English   Publishing type:Research paper (scientific journal)  

    To increase chemical reaction rates, general solutions include increasing the concentration/temperature and introducing catalysts. In this study, the rate constant of an electrophilic metal coordination reaction is accelerated 23-fold on the surface of layered aluminosilicate (LAS), where the reaction substrate (ligand molecule) induces dielectric polarization owing to the polar and anionic surface. According to the Arrhenius plot, the frequency factor (A) is increased by almost three orders of magnitude on the surface. This leads to the conclusion that the collision efficiency between the ligands and metal ions is enhanced on the surface due to the dielectric polarization. This is surprising because one side of the ligand is obscured by the surface, so the collision efficiency is expected to be decreased. This unique method to accelerate the chemical reaction is expected to expand the range of utilization of LASs, which are chemically inert, abundant, and environmentally friendly. The concept is also applicable to other metal oxides which have polar surfaces, which will be useful for various chemical reactions in the future.

    DOI: 10.1002/smll.202205857

    Web of Science

    PubMed

    researchmap

▼display all

Presentations 1

  1. Controlled Growth of large-Sized ZIF-8 Single Crystals Via Solvothermal Method with Effects of Various Temperature. International coauthorship International conference

    Azhar Alowasheeir

    Materials Oceania-2023  2023.9.28 

     More details

    Event date: 2023.7

    Language:English  

    Country:Japan