1. NSLS-II Friday Lunchtime Seminar

    "Reversible Room-Temperature Fluoride-Ion Insertion in a Tunnel-Structured Transition Metal Oxide Host"

    Presented by Wasif Zaheer, Texas A&M University, TX

    Friday, September 18, 2020, 12 pm

    Hosted by: Ignace Jarrige

    An energy storage paradigm orthogonal to Li-ion battery chemistries can be conceptualized by employing anions as the primary charge carriers. F-ion conversion chemistries show promise but have limited cyclability as a result of the significant change in volume of active electrodes upon metal−metal fluoride interconversion. In contrast, the exploration of insertion chemistries has been stymied by the lack of hosts amenable to reversible F-ion insertion at room temperature. In this study, we showed reversible and homogeneous topochemical insertion/deinsertion and bulk diffusion of F ions within the one-dimensional tunnels of sub-micrometer-sized FeSb2O4 particles at room temperature. The insertion of F ions is evidenced by formal oxidation of the iron centers from Fe2+ to Fe3+ with a lattice volume contraction of