start-ver=1.4 cd-journal=joma no-vol=2 cd-vols= no-issue=10 article-no= start-page=4417 end-page=4420 dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200824 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Bottom-up synthesis of nitrogen-doped nanocarbons by a combination of metal catalysis and a solution plasma process en-subtitle= kn-subtitle= en-abstract= kn-abstract=We aimed to develop the bottom-up synthesis of nanocarbons with specific functions from molecules without any leaving group, halogen atom and boronic acid, by employing a metal catalyst under solution plasma irradiation. Pyridine was used as a source of carbon. In the presence of a Pd catalyst, the plasma treatment enabled the synthesis of N-doped carbons with a pyridinic configuration, which worked as an active catalytic site for the oxygen reduction reaction. en-copyright= kn-copyright= en-aut-name=ZhouYang en-aut-sei=Zhou en-aut-mei=Yang kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Research Core for Interdisciplinary Sciences, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=363 cd-vols= no-issue= article-no= start-page=137257 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20201210 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Sophisticated rGO synthesis and pre-lithiation unlocking full-cell lithium-ion battery high-rate performances en-subtitle= kn-subtitle= en-abstract= kn-abstract=For the application to portable devices and storage of renewable energies, high-performance lithium-ion batteries are in great demand. To this end, the development of high-performance electrode materials has been actively investigated. However, even if new materials exhibit high performance in a simple evaluation, namely half-cell tests, it is often impossible to obtain satisfactory performance with an actual battery (full cell). In this study, the structure of graphene analogs is modified in various ways to change crystallinity, disorder, oxygen content, electrical conductivity, and specific surface area. These graphene analogs are evaluated as negative electrodes for lithium-ion batteries, and we found reduced graphene oxide prepared by combination of chemical reduction and thermal treatment was the optimum. In addition, a full cell is fabricated by combining it with LiCoO2 modified with BaTiO3, which is applicable to high-speed charge?discharge cathode material developed in our previous research. In general, pre-lithiation is performed for the anode when assembling full cells. In this study, we optimized a "direct pre-lithiation" method in which the electrode and lithium foil were in direct contact before assembling a full cell, and created a lithium-ion battery with an output of 293 Wh kg?1 at 8,658 W kg?1. en-copyright= kn-copyright= en-aut-name=Camp?onBeno?t Denis Louis en-aut-sei=Camp?on en-aut-mei=Beno?t Denis Louis kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=YoshikawaYumi en-aut-sei=Yoshikawa en-aut-mei=Yumi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TeranishiTakashi en-aut-sei=Teranishi en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=4 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= en-keyword=Graphene kn-keyword=Graphene en-keyword=Lithium-ion battery kn-keyword=Lithium-ion battery en-keyword=Full-cell kn-keyword=Full-cell en-keyword=LiCoO2 kn-keyword=LiCoO2 en-keyword=High-rate kn-keyword=High-rate END start-ver=1.4 cd-journal=joma no-vol=12 cd-vols= no-issue=42 article-no= start-page=21780 end-page=21787 dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200928 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Iron nanoparticle templates for constructing 3D graphene framework with enhanced performance in sodium-ion batteries en-subtitle= kn-subtitle= en-abstract= kn-abstract=This study examines the synthesis and electrochemical performance of three-dimensional graphene for Li-ion batteries and Na-ion batteries. The in situ formation of iron hydroxide nanoparticles (Fe(OH)x NPs) of various weights on the surface of graphene oxide, followed by thermal treatment at elevated temperature and washing using hydrochloric acid, furnished 3D graphene. The characterization studies confirmed the prevention of graphene layer stacking by over 90% compared with thermal treatment without Fe(OH)x. The electrochemical performance of the 3D graphene was evaluated as a counter electrode for lithium metal and sodium metal in a half-cell configuration. This material showed good performances with a charging capacity of 507 mA h g?1 at 372 mA g?1 in Li-ion batteries and 252 mA h g?1 at 100 mA g?1 in Na-ion batteries, which is 1.4 and 1.9 times higher, respectively, than the graphene prepared without Fe(OH)x templates. en-copyright= kn-copyright= en-aut-name=Camp?onBeno?t D. L. en-aut-sei=Camp?on en-aut-mei=Beno?t D. L. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=WangChen en-aut-sei=Wang en-aut-mei=Chen kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= affil-num=1 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= affil-num=2 en-affil=Research Core for Interdisciplinary Sciences, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Natural Science and Technology, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=11 cd-vols= no-issue=23 article-no= start-page=5866 end-page=5873 dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200601 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Carbon-rich materials with three-dimensional ordering at the angstrom level en-subtitle= kn-subtitle= en-abstract= kn-abstract=Carbon-rich materials, which contain over 90% carbon, have been mainly synthesized by the carbonization of organic compounds. However, in many cases, their original molecular and ordered structures are decomposed by the carbonization process, which results in a failure to retain their original three-dimensional (3D) ordering at the angstrom level. Recently, we successfully produced carbon-rich materials that are able to retain their 3D ordering at the angstrom level even after the calcination of organic porous pillar[6]arene supramolecular assemblies and cyclic porphyrin dimer assemblies. Other new pathways to prepare carbon-rich materials with 3D ordering at the angstrom level are the controlled polymerization of designed monomers and redox reaction of graph. Electrocatalytic application using these materials is described. en-copyright= kn-copyright= en-aut-name=FaShixin en-aut-sei=Fa en-aut-mei=Shixin kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=YamamotoMasanori en-aut-sei=Yamamoto en-aut-mei=Masanori kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NishiharaHirotomo en-aut-sei=Nishihara en-aut-mei=Hirotomo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=SakamotoRyota en-aut-sei=Sakamoto en-aut-mei=Ryota kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=KamiyaKazuhide en-aut-sei=Kamiya en-aut-mei=Kazuhide kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=OgoshiTomoki en-aut-sei=Ogoshi en-aut-mei=Tomoki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil=Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University kn-affil= affil-num=2 en-affil=Institute of Multidisciplinary Research for Advanced Materials, Tohoku University kn-affil= affil-num=3 en-affil=Institute of Multidisciplinary Research for Advanced Materials, Tohoku University kn-affil= affil-num=4 en-affil=Department of Energy and Hydrocarbon Chemistry, Graduate School of Engineering, Kyoto University kn-affil= affil-num=5 en-affil=Graduate School of Engineering Science, Osaka University kn-affil= affil-num=6 en-affil=Research Core for Interdisciplinary Sciences, Okayama University kn-affil= affil-num=7 en-affil=Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=8 cd-vols= no-issue=2 article-no= start-page=238 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200219 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Structural Optimization of Alkylbenzenes as Graphene Dispersants en-subtitle= kn-subtitle= en-abstract= kn-abstract=Among the several methods of producing graphene, the liquid-phase exfoliation of graphite is attractive because of a simple and easy procedure, being expected for mass production. The dispersibility of graphene can be improved by adding a dispersant molecule that interacts with graphene, but the appropriate molecular design has not been proposed. In this study, we focused on aromatic compounds with alkyl chains as dispersing agents. We synthesized a series of alkyl aromatic compounds and evaluated their performance as a dispersant for graphene. The results suggest that the alkyl chain length and solubility in the solvent play a vital role in graphene dispersion. en-copyright= kn-copyright= en-aut-name=TakedaShimpei en-aut-sei=Takeda en-aut-mei=Shimpei kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= affil-num=1 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= affil-num=2 en-affil=Graduate School of Natural Science & Technology, Okayama University kn-affil= en-keyword=graphene kn-keyword=graphene en-keyword=graphite kn-keyword=graphite en-keyword=dispersant kn-keyword=dispersant en-keyword=alkylbenzene kn-keyword=alkylbenzene en-keyword=liquid-phase exfoliation kn-keyword=liquid-phase exfoliation END start-ver=1.4 cd-journal=joma no-vol=104 cd-vols= no-issue= article-no= start-page=106475 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20190731 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Bipolar anodic electrochemical exfoliation of graphite powders en-subtitle= kn-subtitle= en-abstract= kn-abstract=The electrochemical exfoliation of graphite has attracted considerable attention as a method for large-scale, rapid production of graphene and graphene oxide (GO). As exfoliation typically requires direct electrical contact, and is limited by the shape and/or size of the starting graphite, treatment of small graphite particles and powders, the typical form available commercially, is extremely difficult. In this study, GO nanosheets were successfully prepared from small graphite particles and powders by a bipolar electrochemical process. Graphite samples were placed between two platinum feeder electrodes, and a constant current was applied between the feeder electrodes using dilute sulfuric acid as the electrolyte. Optical microscopy, atomic force microscopy, X-ray diffractometry, Raman spectroscopy, and X-ray photoelectron spectroscopy were employed to examine the samples obtained after electrolysis. The results obtained from these analyses confirmed that anodic electrochemical exfoliation occurs in the graphite samples, and the exfoliated samples are basically highly crystalline GO nanosheets with a low degree of oxidation (C/O?=?3.6?5.3). This simple electrochemical method is extremely useful for preparing large amounts of graphene and GO from small particles of graphite. en-copyright= kn-copyright= en-aut-name=HashimotoHideki en-aut-sei=Hashimoto en-aut-mei=Hideki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=MuramatsuYusuke en-aut-sei=Muramatsu en-aut-mei=Yusuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=AsohHidetaka en-aut-sei=Asoh en-aut-mei=Hidetaka kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Applied Chemistry, School of Advanced Engineering, Kogakuin University kn-affil= affil-num=2 en-affil=Department of Applied Chemistry, School of Advanced Engineering, Kogakuin University kn-affil= affil-num=3 en-affil=Research Core for Interdisciplinary Sciences, Okayama University kn-affil= affil-num=4 en-affil=Department of Applied Chemistry, School of Advanced Engineering, Kogakuin University kn-affil= en-keyword=Graphite kn-keyword=Graphite en-keyword=Graphene kn-keyword=Graphene en-keyword=Graphene oxide kn-keyword=Graphene oxide en-keyword=Electrochemical exfoliation kn-keyword=Electrochemical exfoliation en-keyword=Anode kn-keyword=Anode en-keyword=Bipolar electrochemistry kn-keyword=Bipolar electrochemistry END start-ver=1.4 cd-journal=joma no-vol=29 cd-vols= no-issue=5 article-no= start-page=2150 end-page=2156 dt-received= dt-revised= dt-accepted= dt-pub-year=2017 dt-pub=20170302 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Real-Time, in Situ Monitoring of the Oxidation of Graphite: Lessons Learned en-subtitle= kn-subtitle= en-abstract= kn-abstract= Graphite oxide (GO) and its constituent layers (i.e., graphene oxide) display a broad range of functional groups and, as such, have attracted significant attention for use in numerous applications. GO is commonly prepared using the gHummers methodh or a variant thereof in which graphite is treated with KMnO4 and various additives in H2SO4. Despite its omnipresence, the underlying chemistry of such oxidation reactions is not well understood and typically affords results that are irreproducible and, in some cases, unsafe. To overcome these limitations, the oxidation of graphite under Hummers-type conditions was monitored over time using in situ X-ray diffraction and in situ X-ray absorption near edge structure analyses with synchrotron radiation. In conjunction with other atomic absorption spectroscopy, UV?vis spectroscopy and elemental analysis measurements, the underlying mechanism of the oxidation reaction was elucidated, and the reaction conditions were optimized. Ultimately, the methodology for reproducibly preparing GO on large scales using only graphite, H2SO4, and KMnO4 was developed and successfully adapted for use in continuous flow systems. en-copyright= kn-copyright= en-aut-name=MorimotoNaoki en-aut-sei=Morimoto en-aut-mei=Naoki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=SuzukiHideyuki en-aut-sei=Suzuki en-aut-mei=Hideyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TakeuchiYasuo en-aut-sei=Takeuchi en-aut-mei=Yasuo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KawaguchiShogo en-aut-sei=Kawaguchi en-aut-mei=Shogo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=KunisuMasahiro en-aut-sei=Kunisu en-aut-mei=Masahiro kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=BielawskiChristopher W. en-aut-sei=Bielawski en-aut-mei=Christopher W. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=NishinaYuta en-aut-sei=Nishina en-aut-mei=Yuta kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= affil-num=1 en-affil=Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Division of Pharmaceutical Sciences, Okayama University kn-affil= affil-num=2 en-affil=Research Core for Interdisciplinary Sciences, Okayama University kn-affil= affil-num=3 en-affil=Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Division of Pharmaceutical Sciences, Okayama Universit kn-affil= affil-num=4 en-affil=Japan Synchrotron Radiation Research Institute (JASRI), SPring-8 kn-affil= affil-num=5 en-affil=Toray Research Center, Inc., Surface Science Laboratories kn-affil= affil-num=6 en-affil=Center for Multidimensional Carbon Materials (CMCM), Institute for Basic Science (IBS) kn-affil= affil-num=7 en-affil=Research Core for Interdisciplinary Sciences, Okayama University kn-affil= END