title: New Mechanistic Insights on Na-Ion Storage in Nongraphitizable Carbon.
abstract: Nongraphitizable carbon, also known as hard carbon, is considered one of the most promising anodes for the emerging Na-ion batteries. The current mechanistic understanding of Na-ion storage in hard carbon is based on the "card-house" model first raised in the early 2000s. This model describes that Na-ion insertion occurs first through intercalation between graphene sheets in turbostratic nanodomains, followed by Na filling of the pores in the carbon structure. We tried to test this model by tuning the sizes of turbostratic nanodomains but revealed a correlation between the structural defects and Na-ion storage. Based on our experimental data, we propose an alternative perspective for sodiation of hard carbon that consists of Na-ion storage at defect sites, by intercalation and last via pore-filling.
authors.affiliation: Department of Chemistry, Oregon State University , Corvallis, Oregon 97331-4003, United States.
authors.forename: Clement
authors.initials: C
authors.lastname: Bommier
authors.affiliation: Department of Chemistry, Oregon State University , Corvallis, Oregon 97331-4003, United States.
authors.forename: Todd Wesley
authors.initials: TW
authors.lastname: Surta
authors.affiliation: Department of Chemistry, Oregon State University , Corvallis, Oregon 97331-4003, United States.
authors.forename: Michelle
authors.initials: M
authors.lastname: Dolgos
authors.affiliation: Department of Chemistry, Oregon State University , Corvallis, Oregon 97331-4003, United States.
authors.forename: Xiulei
authors.initials: X
authors.lastname: Ji
keywords: Na-ion batteries; defect sites; hard carbon; intercalation; reaction mechanism