Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems
In this work, reactions of either LiBH\(_4\), ZnCl\(_2\) or Zn\(_3\)N\(_2\) with LiNH\(_2\) have been studied. The presence of CoO significantly affected the products and hydrogen release on heating mixtures of χLiBH\(_4\)-γLiNH\(_2\). The ratios of the l4\(_1\)/amd and the P2\(_1\)/c polymorphs of...
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ndltd-bl.uk-oai-ethos.bl.uk-6853912019-04-03T06:42:13ZHydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systemsNguyen, Trang Thi Thu2016In this work, reactions of either LiBH\(_4\), ZnCl\(_2\) or Zn\(_3\)N\(_2\) with LiNH\(_2\) have been studied. The presence of CoO significantly affected the products and hydrogen release on heating mixtures of χLiBH\(_4\)-γLiNH\(_2\). The ratios of the l4\(_1\)/amd and the P2\(_1\)/c polymorphs of Li\(_3\)BN\(_2\) in the products have been changed under different conditions studied. On addition of CoO, the temperature of hydrogen release from the χLiBH\(_4\)-γLiNH\(_2\) systems was greatly reduced, starting from 100°C and peaking around 250°C, much lower than 240°C and 330°C without catalyst. Ball-milling helped to improve the amounts of hydrogen desorbed from 3–4 wt% up to ≥10 wt%. In the reactions of ZnCl\(_2\) + nLiNH\(_2\) (where \(\textit n\) = 2–6), main products were LiCl, Zn\(_3\)N\(_2\), and LiZnN. NH\(_3\) was the main gas released from these reactions and the addition of LiH changed NH\(_3\) into H\(_2\), which was released around 90°C, much lower than in the absence of LiH. A mixture of LiZnN and LiCl obtained from this reaction was partly rehydrogenated to form Li\(_2\)NH and Zn. The reaction of Zn\(_3\)N\(_2\) and LiNH\(_2\) was found to produce pure LiZnN without LiCl. Neither pure LiZnN nor Zn\(_3\)N\(_2\) could be hydrogenated under the conditions tried, but a mixture resulting from the reaction could react with H\(_2\) to form LiNH\(_2\) and Zn. The cyclability of the Li–Zn–N system showed an ability to release and take up gases under different pressure conditions. Mg-doping in LiZnN was examined to improve reversibility of the Li–Zn–N system but was not successful.546QD ChemistryUniversity of Birminghamhttps://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.685391http://etheses.bham.ac.uk//id/eprint/6671/Electronic Thesis or Dissertation |
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546 QD Chemistry Nguyen, Trang Thi Thu Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
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In this work, reactions of either LiBH\(_4\), ZnCl\(_2\) or Zn\(_3\)N\(_2\) with LiNH\(_2\) have been studied. The presence of CoO significantly affected the products and hydrogen release on heating mixtures of χLiBH\(_4\)-γLiNH\(_2\). The ratios of the l4\(_1\)/amd and the P2\(_1\)/c polymorphs of Li\(_3\)BN\(_2\) in the products have been changed under different conditions studied. On addition of CoO, the temperature of hydrogen release from the χLiBH\(_4\)-γLiNH\(_2\) systems was greatly reduced, starting from 100°C and peaking around 250°C, much lower than 240°C and 330°C without catalyst. Ball-milling helped to improve the amounts of hydrogen desorbed from 3–4 wt% up to ≥10 wt%. In the reactions of ZnCl\(_2\) + nLiNH\(_2\) (where \(\textit n\) = 2–6), main products were LiCl, Zn\(_3\)N\(_2\), and LiZnN. NH\(_3\) was the main gas released from these reactions and the addition of LiH changed NH\(_3\) into H\(_2\), which was released around 90°C, much lower than in the absence of LiH. A mixture of LiZnN and LiCl obtained from this reaction was partly rehydrogenated to form Li\(_2\)NH and Zn. The reaction of Zn\(_3\)N\(_2\) and LiNH\(_2\) was found to produce pure LiZnN without LiCl. Neither pure LiZnN nor Zn\(_3\)N\(_2\) could be hydrogenated under the conditions tried, but a mixture resulting from the reaction could react with H\(_2\) to form LiNH\(_2\) and Zn. The cyclability of the Li–Zn–N system showed an ability to release and take up gases under different pressure conditions. Mg-doping in LiZnN was examined to improve reversibility of the Li–Zn–N system but was not successful. |
author |
Nguyen, Trang Thi Thu |
author_facet |
Nguyen, Trang Thi Thu |
author_sort |
Nguyen, Trang Thi Thu |
title |
Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
title_short |
Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
title_full |
Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
title_fullStr |
Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
title_full_unstemmed |
Hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
title_sort |
hydrogen release and absorption in mixed anion lithium amide/lithium ternary nitride systems |
publisher |
University of Birmingham |
publishDate |
2016 |
url |
https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.685391 |
work_keys_str_mv |
AT nguyentrangthithu hydrogenreleaseandabsorptioninmixedanionlithiumamidelithiumternarynitridesystems |
_version_ |
1719014233334611968 |