New Insight on Open‐Structured Sodium Vanadium Oxide as High‐Capacity and Long Life Cathode for Zn–Ion Storage: Structure, Electrochemistry, and First‐Principles Calculation. Issue 40 (1st September 2020)

• Record Type: Journal Article
• Authors: Jo, Jae Hyeon; Aniskevich, Yauhen; Kim, Jongsoon; Choi, Ji Ung; Kim, Hee Jae; Jung, Young Hwa; Ahn, Docheon; Jeon, Tae‐Yeol; Lee, Kug‐Seung; Song, Seok Hyun; Kim, Hyungsub; Ragoisha, Genady; Mazanik, Alexander; Streltsov, Eugene; Myung, Seung‐Taek
• Is Part Of: Advanced energy materials. Volume 10:Issue 40(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-09-01
• Subjects: batteries -- intercalation -- operando -- vanadate -- zinc; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.202001595
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Herein, the promising properties of open‐structured NaV3 O8 as a cathode material for Zn‐ion batteries (ZIBs) are investigated. First‐principles calculations predict the insertion of Zn 2+ (0.74 Å) in NaV3 O8 with an interlayer distance of ≈7 Å, enabling delivery of a high discharge capacity of 353 mAh g −1 at 70 mA g −1 (0.2 C) for 300 cycles in the operating window of 0.3−1.5 V in 1 m Zn(CF3 SO3 )2 aqueous solution. Operando synchrotron X‐ray diffraction, X‐ray absorption near edge structure spectroscopy, and first‐principles calculations validate the insertion of Zn 2+ into the NaV3 O8 structure within the operation range. Moreover, operando synchrotron X‐ray diffraction and operando Raman spectroscopy reveal the formation of layered zinc hydroxytriflate (Zn5 (OH)8 (CF3 SO3 )2 ∙ x H2 O) as a side reaction below 0.8 V on discharge (reduction) and its dissolution into the electrolyte above 0.8 V on charge (oxidation). The formation of the Zn hydroxytriflate interfacial layer increases the charge‐transfer activation energy from 15.5 to 48 kJ mol −1, leading to kinetics fade below 0.8 V. The findings reveal the charge‐storage mechanism for NaV3 O8, which may also be applicable to other vanadate cathodes, providing new insights for the investigation and design of ZIBs. Abstract : New insights on open‐structured NaV3 O8 as a cathode for Zn‐ion storage are provided. Interfacial layer formation is explained via first‐principles calculations, operando synchrotron XRD, and operando Raman spectroscopy.