Abstract
Several yolk-shell-structured CuO-Fe2O3 powders with various Cu/Fe molar ratios have been successfully prepared under equivalent reaction conditions using a one-pot spray pyrolysis process. The Cu and Fe components are uniformly distributed throughout the powders, irrespective of composition. The Brunauer-Emmett-Teller surface areas of the yolk-shell CuO-Fe2O3 systems increased from 5 to 16m2 g-1 if the Cu/Fe molar ratios are decreased from 3:1 to 1:3. The initial discharge and charge capacities of the yolk-shell CuO-Fe 2O3 system (Cu/Fe=1:2), showing maximum values at a constant current density of 1000mA g-1, are 1436 and 1012mA h g -1, respectively. After 130cycles, the discharge capacities of the yolk-shell CuO-Fe2O3 powders with Cu/Fe molar ratios of 1:3, 1:2, 1:1, 2:1, and 3:1 are 1159, 1151, 755, 655, and 651mA h g -1, respectively. The discharge capacities of the yolk-shell and dense powder samples after 50cycles, when subjected to a series of current density increases from 500 to 5000mA g-1, are 735 and 495mA h g -1, respectively. Yolksfest! The effects of composition on the electrochemical properties of a yolk-shell-structured CuO-Fe2O 3 powder system are investigated. The unique structure of the yolk-shell CuO-Fe2O3 powders results in improved mechanical stability over repeated lithium ion insertion and extraction processes, and in improved rate performance and cycling properties at high current densities.
| Original language | English |
|---|---|
| Pages (from-to) | 2299-2303 |
| Number of pages | 5 |
| Journal | ChemSusChem |
| Volume | 6 |
| Issue number | 12 |
| DOIs | |
| Publication status | Published - 2013 Dec |
| Externally published | Yes |
Keywords
- batteries
- electrodes
- nanostructures
- spray pyrolysis
- yolk-shell powders
ASJC Scopus subject areas
- Environmental Chemistry
- Chemical Engineering(all)
- Materials Science(all)
- Energy(all)