The structure of polyanionic materials is conventionally known to be free of transition metal migration and structurally stable when storing/releasing sodium ions. Herein, the observation of enhanced cycling stability of a typical polyanionic cathode, Na3VCr(PO4)3(NVCP) at lower temperature (−15 °C vs 30 °C), triggers the exploration of its structural origins with a surprising finding that the migratable nature of vanadium in NVCP leads to detrimental structural degradation of the polyanionic host upon cycling. The correlation between long range and short range structural change associated with this atomic migration is established via a strong combination of various in situ
Enhancing electron correlation in a weakly interacting topological system has great potential to promote correlated topological states of matter with extraordinary quantum properties. Here, the enhancement of electron correlation in a prototypical topological metal, namely iridium dioxide (IrO2), via doping with 3d transition metal vanadium is demonstrated. Single‐crystalline vanadium‐doped IrO2nanowires are synthesized through chemical vapor deposition where the nanowire yield and morphology are improved by creating rough surfaces on substrates. Vanadium doping leads to a dramatic decrease in Raman intensity without notable peak broadening, signifying the enhancement of electron correlation. The enhanced electron correlation is further evidenced by transport studies where the electrical resistivity is greatly increased and follows an unusual dependence on the temperature (
- NSF-PAR ID:
- 10382177
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 10
- Issue:
- 2
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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