Structural and Electrochemical Characterization of Zn1−xFexO—Effect of Aliovalent Doping on the Li+ Storage Mechanism
AbstractIn order to further improve the energy and power density of state-of-the-art lithium-ion batteries (LIBs), new cell chemistries and, therefore, new active materials with alternative storage mechanisms are needed. Herein, we report on the structural and electrochemical characterization of Fe-doped ZnO samples with varying dopant concentrations, potentially serving as anode for LIBs (Rechargeable lithium-ion batteries). The wurtzite structure of the Zn1−xFexO samples (with x ranging from 0 to 0.12) has been refined via the Rietveld method. Cell parameters change only slightly with the Fe content, whereas the crystallinity is strongly affected, presumably due to the presence of defects induced by the Fe3+ substitution for Zn2+. XANES (X-ray absorption near edge structure) data recorded ex situ for Zn0.9Fe0.1O electrodes at different states of charge indicated that Fe, dominantly trivalent in the pristine anode, partially reduces to Fe2+ upon discharge. This finding was supported by a detailed galvanostatic and potentiodynamic investigation of Zn1−xFexO-based electrodes, confirming such an initial reduction of Fe3+ to Fe2+ at potentials higher than 1.2 V (vs. Li+/Li) upon the initial lithiation, i.e., discharge. Both structural and electrochemical data strongly suggest the presence of cationic vacancies at the tetrahedral sites, induced by the presence of Fe3+ (i.e., one cationic vacancy for every two Fe3+ present in the sample), allowing for the initial Li+ insertion into the ZnO lattice prior to the subsequent conversion and alloying reaction. View Full-Text
Scifeed alert for new publicationsNever miss any articles matching your research from any publisher
- Get alerts for new papers matching your research
- Find out the new papers from selected authors
- Updated daily for 49'000+ journals and 6000+ publishers
- Define your Scifeed now
Giuli, G.; Eisenmann, T.; Bresser, D.; Trapananti, A.; Asenbauer, J.; Mueller, F.; Passerini, S. Structural and Electrochemical Characterization of Zn1−xFexO—Effect of Aliovalent Doping on the Li+ Storage Mechanism. Materials 2018, 11, 49.
Giuli G, Eisenmann T, Bresser D, Trapananti A, Asenbauer J, Mueller F, Passerini S. Structural and Electrochemical Characterization of Zn1−xFexO—Effect of Aliovalent Doping on the Li+ Storage Mechanism. Materials. 2018; 11(1):49.Chicago/Turabian Style
Giuli, Gabriele; Eisenmann, Tobias; Bresser, Dominic; Trapananti, Angela; Asenbauer, Jakob; Mueller, Franziska; Passerini, Stefano. 2018. "Structural and Electrochemical Characterization of Zn1−xFexO—Effect of Aliovalent Doping on the Li+ Storage Mechanism." Materials 11, no. 1: 49.
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.