The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform
Chang Woo Lee - One of the best experts on this subject based on the ideXlab platform.
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tin selenide n doped carbon composite as a conversion and alloying type anode for sodium ion batteries
Journal of Alloys and Compounds, 2020Co-Authors: Nitheesha Shaji, P Santhoshkumar, Hyeong Seop Kang, Murugan Nanthagopal, Jae Woo Park, Sekar Praveen, Gyu Sang Sim, Chenrayan Senthil, Chang Woo LeeAbstract:Abstract Sodium-ion batteries (SIBs) have attracted remarkable attention since they are considered a low-cost alternative for lithium-ion batteries (LIBs) for large scale energy storage system applications. Tin Selenides such as SnSe and SnSe2 are earth-abundant, environmentally friendly, chemically stable, and capable candidates as the negative electrode for SIBs, in which the capacity is provided by a conversion reaction together with the alloying mechanism. However, these materials suffer from low conductivity, drastic volume changes, and aggregation of particles during the electrochemical reaction, which lead to poor cycling performance, hindering their practical application. The combination of tin selenide with conductive carbon is an effective strategy to overcome the issues mentioned above. Herein, we report tin selenide/N-doped carbon composite as an anode material for SIBs fabricated by solvothermal synthesis followed by a dry solid state method and calcination. The as-prepared tin selenide/N-doped carbon composite electrode delivers an initial discharge capacity of 460 mAh g−1 and maintained a discharge capacity of 348 mAh g−1 at the end of the 100th cycle at a current density of 200 mA g−1, which is almost 3.5 times higher in discharge capacity than the pristine electrodes. Moreover, the composite electrode exhibits outstanding rate capability compared to pristine tin selenide with a discharge capacity of 234 mAh g−1 even at a high current density of 1600 mA g−1. N-doped carbon provides improved conductivity as well as buffering the volume change during sodiation/desodiation, resulting in an overall enhancement of electrochemical performance.
Antonella Capperucci - One of the best experts on this subject based on the ideXlab platform.
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bis trimethylsilyl selenide in the selective synthesis of β hydroxy β mercapto and β amino diorganyl diSelenides and Selenides through ring opening of strained heterocycles
ChemInform, 2015Co-Authors: Damiano Tanini, Alessandro Deglinnocenti, Antonella CapperucciAbstract:A novel approach to the synthesis of β-substituted dialkyl diSelenides and Selenides is described through reaction of bis(trimethylsilyl)selenide with epoxides, thiiranes, and aziridines catalyzed by tetrabutylammonium fluoride.
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bis trimethylsilyl selenide in the selective synthesis of β hydroxy β mercapto and β amino diorganyl diSelenides and Selenides through ring opening of strained heterocycles
European Journal of Organic Chemistry, 2015Co-Authors: Damiano Tanini, Alessandro Deglinnocenti, Antonella CapperucciAbstract:A novel approach to the synthesis of β-substituted dialkyl diSelenides and Selenides is described through reaction of bis(trimethylsilyl)selenide with epoxides, thiiranes, and aziridines catalyzed by tetrabutylammonium fluoride. Selective formation of a wide variety of β-hydroxy, β-mercapto, and β-amino diSelenides and Selenides is achieved by controlling the reaction conditions in the regioselective attack of the silyl selenide onto the ring-strained heterocycles. All reactions occur in a highly regioselective and enantioconservative manner, affording the title compounds with good to high yields. Selenium-77 NMR chemical shifts were measured to verify the selective formation of the β-substituted diSelenides and Selenides.
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Bis(trimethylsilyl)selenide in the Selective Synthesis of β‐Hydroxy, β‐Mercapto, and β‐Amino Diorganyl DiSelenides and Selenides Through Ring Opening of Strained Heterocycles
European Journal of Organic Chemistry, 2014Co-Authors: Damiano Tanini, Alessandro Degl'innocenti, Antonella CapperucciAbstract:A novel approach to the synthesis of β-substituted dialkyl diSelenides and Selenides is described through reaction of bis(trimethylsilyl)selenide with epoxides, thiiranes, and aziridines catalyzed by tetrabutylammonium fluoride. Selective formation of a wide variety of β-hydroxy, β-mercapto, and β-amino diSelenides and Selenides is achieved by controlling the reaction conditions in the regioselective attack of the silyl selenide onto the ring-strained heterocycles. All reactions occur in a highly regioselective and enantioconservative manner, affording the title compounds with good to high yields. Selenium-77 NMR chemical shifts were measured to verify the selective formation of the β-substituted diSelenides and Selenides.
Nitheesha Shaji - One of the best experts on this subject based on the ideXlab platform.
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tin selenide n doped carbon composite as a conversion and alloying type anode for sodium ion batteries
Journal of Alloys and Compounds, 2020Co-Authors: Nitheesha Shaji, P Santhoshkumar, Hyeong Seop Kang, Murugan Nanthagopal, Jae Woo Park, Sekar Praveen, Gyu Sang Sim, Chenrayan Senthil, Chang Woo LeeAbstract:Abstract Sodium-ion batteries (SIBs) have attracted remarkable attention since they are considered a low-cost alternative for lithium-ion batteries (LIBs) for large scale energy storage system applications. Tin Selenides such as SnSe and SnSe2 are earth-abundant, environmentally friendly, chemically stable, and capable candidates as the negative electrode for SIBs, in which the capacity is provided by a conversion reaction together with the alloying mechanism. However, these materials suffer from low conductivity, drastic volume changes, and aggregation of particles during the electrochemical reaction, which lead to poor cycling performance, hindering their practical application. The combination of tin selenide with conductive carbon is an effective strategy to overcome the issues mentioned above. Herein, we report tin selenide/N-doped carbon composite as an anode material for SIBs fabricated by solvothermal synthesis followed by a dry solid state method and calcination. The as-prepared tin selenide/N-doped carbon composite electrode delivers an initial discharge capacity of 460 mAh g−1 and maintained a discharge capacity of 348 mAh g−1 at the end of the 100th cycle at a current density of 200 mA g−1, which is almost 3.5 times higher in discharge capacity than the pristine electrodes. Moreover, the composite electrode exhibits outstanding rate capability compared to pristine tin selenide with a discharge capacity of 234 mAh g−1 even at a high current density of 1600 mA g−1. N-doped carbon provides improved conductivity as well as buffering the volume change during sodiation/desodiation, resulting in an overall enhancement of electrochemical performance.
Olivier F X Donard - One of the best experts on this subject based on the ideXlab platform.
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Formation and volatilisation of alkyl-iodides and -Selenides in macrotidal estuaries
Biogeochemistry, 2002Co-Authors: Emmanuel Tessier, David Amouroux, G. Abril, E. Lemaire, Olivier F X DonardAbstract:The occurrence of alkylated volatile iodide and selenide species was evidenced and investigated in water, sediments and overlying atmosphere of three major European estuaries, such as the Gironde (F), the Rhine (NL) and the Scheldt (B/NL), along with the salinity gradient. For iodine, up to eight volatile species were observed as alkyl-iodides in estuarine waters. The major one (ca. 40%) was methyl-iodide (MeI) with average seasonal concentrations ranging from 1 to 100 pmol l-1. Other species observed were found to correspond to several halomethane derivatives and light alkyl-iodide species. For selenium, dimethyl selenide (Me2Se) was the main compound (ca. 90%) over three methyl-Selenides encountered in estuarine waters. Me2Se average seasonal concentrations were found to range between 0.2 and 100 pmol l-1 in the water column. The occurrence of methylated iodides and Selenides seems to be mainly related to the algae's biomass turnover as indicated by photosynthetic pigment tracers (i.e. chlorophyll a and phaeopigments) and seasonal variation of surface water concentrations. The production and release of gaseous iodide and selenide compounds may then result from natural biological pathways leading to the methylation of their inorganic form. Finally, significant volatilisation rates were evaluated leading to average seasonal flux rates for total volatile iodide and selenide compounds ranging from 4 to 100 and from 1 to 75 nmol m-2 d-1, respectively. Estuarine mass balance estimated from MeI and Me2Se distributions indicates that volatilisation to the atmosphere represents a primary sink for MeI and Me2Se from estuarine surface waters.
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© 2002 Kluwer Academic Publishers. Printed in the Netherlands. Formation and volatilisation of alkyl-iodides and-Selenides in macrotidal estuaries
2000Co-Authors: Emmanuel Tessier, David Amouroux, G. Abril, E. Lemaire, Olivier F X DonardAbstract:Abstract. The occurrence of alkylated volatile iodide and selenide species was evidenced and investigated in water, sediments and overlying atmosphere of three major European estuaries, such as the Gironde (F), the Rhine (NL) and the Scheldt (B/NL), along with the salinity gradient. For iodine, up to eight volatile species were observed as alkyl-iodides in estuarine waters. The major one (ca. 40%) was methyl-iodide (MeI) with average seasonal concen-trations ranging from 1 to 100 pmol l−1. Other species observed were found to correspond to several halomethane derivatives and light alkyl-iodide species. For selenium, dimethyl selenide (Me2Se) was the main compound (ca. 90%) over three methyl-Selenides encountered in estuarine waters. Me2Se average seasonal concentrations were found to range between 0.2 and 100 pmol l−1 in the water column. The occurrence of methylated iodides and Selenides seems to be mainly related to the algae’s biomass turnover as indicated by photosynthetic pigment tracers (i.e. chlorophyll a and phaeopigments) and seasonal variation of surface water concentrations. The production and release of gaseous iodide and selenide compounds may then result from natural biological pathways leading to the methylation of their inorganic form. Finally, significant volatilisation rates were evaluated leading to average seasonal flux rates for total volatile iodide and selenide compounds ranging from 4 to 100 and from 1 to 75 nmol m−2 d−1, respectively. Estuarine mass balance estimated from MeI and Me2Se distributions indicates that volatilisation to the atmosphere represents a primary sink for MeI and Me2Se from estuarine surface waters
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Maritime emission of selenium to the atmosphere in Eastern Mediterranean seas
Geophysical Research Letters, 1996Co-Authors: David Amouroux, Olivier F X DonardAbstract:Results presented in this article report the first assessment of at least 3 volatile selenium species (MeSeH, DMSe, DMDSe) in marine water and air. Dimethyl selenide (DMSe) was the main compound encountered and the total concentration of the volatile Selenides was found to be correlated with the marine plankton biomass as measured through chlorophyll a content. Estimation of a net selenium flux from the ocean to the marine atmosphere has been established. This gaseous flux corroborates previous hypotheses on selenium cycling and indicates that maritime emissions are a major source of selenium to the atmosphere in the Mediterranean basin.
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Maritime emission of selenium to the atmosphere in eastern Mediterranean seas
Geophysical Research Letters, 1996Co-Authors: David Amouroux, Olivier F X DonardAbstract:Results presented in this article report the first assessment of at least 3 volatile selenium species (MeSeH, DMSe, DMDSe) in marine water and air. Dimethyl selenide (DMSe) was the main compound encountered and the total concentration of the volatile Selenides was found to be correlated with the marine plankton biomass as measured through chlorophyll a content. Estimation of a net selenium flux from the ocean to the marine atmosphere has been established. This gaseous flux corroborates previous hypotheses on selenium cycling and indicates that maritime emissions are a major source of selenium to the atmosphere in the Mediterranean basin. Copyright 1996 by the American Geophysical Union.
C W Liu - One of the best experts on this subject based on the ideXlab platform.
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reaction of vinyl Selenides with secondary phosphines and elemental selenium one pot selective synthesis of a new family of diselenophosphinic se esters
Heteroatom Chemistry, 2014Co-Authors: Alexander V Artemev, Nina K. Gusarova, Nataliya A Chernysheva, Svetlana V Yasko, Jianhong Liao, C W Liu, A I Albanov, B A TrofimovAbstract:Alkyl vinyl Selenides react with diverse secondary phosphines and elemental selenium in a 1.1:1:2 molar ratio (120–124°C, 20–40 min, 1,4-dioxane) to afford selectively earlier unknown diselenophosphinic Se-esters, R2P(Se)SeCH(Me)SeR´, in 82–99% yield. This three-component atom-economic reaction proceeds via intermediate formation of diselenophosphinic acid R2P(Se)SeH (generated from secondary phosphine and selenium), which adds to the double bond of vinyl selenide in a Markovnikov manner to give the target products.
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Reactivities of Secondary Phosphine Selenides Cp(CO)2FeP(Se)(OR)2: Formation of a Diiodine Charge Transfer Adduct and Se-Methylation
Organometallics, 2009Co-Authors: Ling-song Chiou, Ching-shiang Fang, Bijay Sarkar, Ling-kang Liu, Max K. Leong, C W LiuAbstract:The organoiron-substituted phosphine Selenides Cp(CO)2FeP(Se)(OR)2 (R = iPr (1a), nPr (1b), Et (1c)) were synthesized. The metalloligands, capable of reacting as nucleophiles toward Me3OBF4, formed Se-methylated products (2a−c). Upon reaction with diiodine, they formed spokelike charge-transfer adducts (3a−c). Among them 1b, 2b, and 3a were structurally authenticated, and 3a was the first structurally characterized, charge-transfer spoke adduct of a secondary phosphine selenide with diiodine.
