Supercharging a MnO2 Nanowire : An Amine-Altered Morphology Retains Capacity at High Rates and Mass Loadings
The influence of hexamethylenetetraamine (HMTA) on the morphology of δ-MnO2 and its properties for electrical energy storage are investigated-specifically for ultrathick δ-MnO2 layers in the micron scale. Planar arrays of goldδ-MnO2, core@shell nanowires, were prepared by electrodeposition with and...
| Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1992. - 33(2017), 37 vom: 19. Sept., Seite 9324-9332 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2017
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| Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
| Schlagworte: | Journal Article Research Support, U.S. Gov't, Non-P.H.S. |
| Zusammenfassung: | The influence of hexamethylenetetraamine (HMTA) on the morphology of δ-MnO2 and its properties for electrical energy storage are investigated-specifically for ultrathick δ-MnO2 layers in the micron scale. Planar arrays of goldδ-MnO2, core@shell nanowires, were prepared by electrodeposition with and without the HMTA and their electrochemical properties were evaluated. HMTA alters the MnO2 in three ways: First, it creates a more open morphology for the MnO2 coating, characterized by "petals" with a thickness of 6 to 9 nm, rather than much thinner δ-MnO2 sheets seen in the absence of HMTA. Second, the electronic conductivity of the δ-MnO2 is increased by an order of magnitude. Third, δ-MnO2 prepared in HMTA shows a (001) interlayer spacing that is expanded by ≈30% possibly accelerating Li transport. The net effect of "HTMA doping" is to dramatically improve high rate performance, culminating in an increase in the specific capacity for the thickest MnO2 shells examined here by a factor of 15 at 100 mV/s |
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| Beschreibung: | Date Completed 23.07.2018 Date Revised 23.07.2018 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1520-5827 |
| DOI: | 10.1021/acs.langmuir.7b00729 |