3 years ago

Cubic Perovskite Fluoride as Open Framework Cathode for Na-Ion Batteries

Cubic Perovskite Fluoride as Open Framework Cathode for Na-Ion Batteries
Zhengwen Fu, Dingren Shi, Jincang Zhang, Dunping Cao, Congling Yin, Chilin Li
Exploring novel structure prototype and mineral phase, especially open framework material, is crucial to developing high-performance Na-ion battery cathodes in view of potentially faster intrinsic diffusion of Na+ in lattices. Perovskite phases have been widely applied in solar cells, fuel cells, and electrocatalysis; however, they are rarely attempted as energy storage electrode materials. This study proposes pre-expanding perovskite iron fluoride (KFeF3) framework by stuffing large-sized K+ as a channel filler, which is advantageous over Na+, NH4+, and H2O molecule filler in terms of structure robustness, symmetry, and connectivity. K+ stuffing leads to the preservation of a more “regular” cubic phase with fast isotropic 3D diffusion as a consequence of no distortion of FeF6 octahedra during K-Na electrochemical exchange and following Na-insertion cycling. High-rate Na-storage is achievable with a reversible capacity of 110, 70, and 40 mAh g−1 at 0.1, 2, and 10 C, respectively, for this open framework fluoride cathode, benefiting from solid solution electrochemical behavior and high intrinsic diffusion coefficient. It is thought that this rate performance is currently the best among Na-storage fluoride materials. Pervoskite iron fluoride (KFeF3) of open framework is proposed as a high-rate Na-ion battery cathode. Prestuffing large-sized K+ into channels leads to the preservation of cubic phase with fast isotropic 3D diffusion as a consequence of no distortion of FeF6 octahedra during first K-extraction and following Na-storage cycling.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/adfm.201701130

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.