Mohammad Razaul Karim, Kazuto Hatakeyama, Takeshi Matsui, Hiroshi Takehira et al.
We measured the proton conductivity of bulk graphite oxide (GO'), a graphene oxide/proton hybrid (GO-H), and a graphene oxide (GO) nanosheet for the first time. GO is a well-known electronic insulator, but for proton conduction we observed the reverse trend, as it exhibited superionic conductivity. ...
Yusuke Murashima, Mohammad Razaul Karim, Ryo Furue, Takeshi Matsui et al.
Reduced graphene oxide–transition metal hybrids were accomplished to deposit a p-type semiconductor films on conductive glass for acetaldehyde sensing.
Yusuke Murashima, Mohammad Razaul Karim, Naoto Saigo, Hiroshi Takehira et al.
Graphene oxide and reduced graphene oxide hybrids with spin crossover complexes show the coexistence of electron conduction and unique magnetic behaviors.
Yukino Ikeda, Mohammad Razaul Karim, Hiroshi Takehira, Takeshi Matsui et al.
Abstract Graphene oxide–alkylamine (GO–Cnamine; n = 0, 1, 2, 3, 4, 6, 8, 10, 12, 14, 16, and 18) hybrids were synthesized and found to be stable through bonding between the N-terminals of the amine precursors and the epoxy sites of graphene. The hybrids were characterized by X-ray photoelectron spec...
Yukino Ikeda, Mohammad Razaul Karim, Hiroshi Takehira, Takeshi Matsui et al.
Abstract Proton conductivity of graphene oxide (GO) has been reduced in graphene oxide–metal ion hybrids (GO–M; M = K+, Al3+, Zn2+, Fe3+, Cr3+, Co2+, Pr3+, Ce3+, and Tb3+). As the hybrids contain doped metal ions, we propose their possibility as catalyst and electrodes in sensing devices.
Hiroshi Takehira, Mohammad Razaul Karim, Yuta Shudo, Masahiro Fukuda et al.
Abstract Chlorine on graphene (G) matrices was doped by pulsed plasma stimulation on graphite electrode submerged in organochlorine solvents (CH 2 Cl 2 , CHCl 3 , CCl 4 ). The study of work function by Kelvin probe force microscopy (KPFM) measurement clearly indicates that Cl-doped G behave like sem...
Md. Saidul Islam, Mohammad Razaul Karim, Kazuto Hatakeyama, Hiroshi Takehira et al.
A highly stable proton conductor has been developed from carbon sphere oxide (CSO). Carbon sphere (CS) generated from sucrose was oxidized successfully to CSO using Hummers' graphite oxidation technique. At room temperature and 90 % relative humidity, the proton conductivity of thin layer CSO on mic...
Yukino Ikeda, Mohammad Razaul Karim, Hiroshi Takehira, Kazuto Hatakeyama et al.
Abstract We report the photocatalytic activities of graphene oxide–alkylated amines (GO–An; GO: graphene oxide and An: alkylamine with n carbons in the alkyl group; n = 0, 1, 4, and 8). The hybrids were synthesized through facile, quick, and reproducible methods and were characterized by Fourier tra...
Hiroshi Takehira, Md. Saidul Islam, Mohammad Razaul Karim, Yuta Shudo et al.
Abstract Both p‐ and n‐type field effect transistors (FET) properties have been observed in undoped reduced graphene oxide (rGO). Short and long time exposure of GO during photo reduction results in the formation of respective p‐ and n‐type rGO semiconductor. Achieving duel behavior of this type in ...
Mohammad Razaul Karim, Md. Saidul Islam, Nurun Nahar Rabin, Hiroshi Takehira et al.
Abstract Within the nanopores, junctions and interlayer void space (IVS) in graphene oxide film (GOf), we report that IVS function as the key semipermeable site during sieving. The GOf could filter only dye molecules having nanometer‐ranged dimensions. Tinier hydrated ions with angstrom‐ranged dimen...
Mohammad Razaul Karim, Hiroshi Takehira, Mohammed M. Rahman, Abdullah M. Asiri et al.
Takeshi Matsui, Mohammad Razaul Karim, Hiroshi Takehira, Masaaki Nakamura et al.
A graphene oxide (GO) and ruthenium(II) complex with bromine-substituted terpyridine ligand, [Ru(Br-terpy)2]Cl2 (Br-terpy: 4′-bromo-2,2′:6′,2′′-terpyridine), reacts to form a GO–[Ru(Br-terpy)2]2+ hybrid, which after photoreduction turns to the reduced graphene oxide (rGO)-based hybrid rGO–[Ru(Br-ter...