title: Real-Time X-ray Imaging Reveals Interfacial Growth, Suppression, and Dissolution of Zinc Dendrites Dependent on Anions of Ionic Liquid Additives for Rechargeable Battery Applications.
abstract: The dynamic interfacial growth, suppression, and dissolution of zinc dendrites have been studied with the imidazolium ionic liquids (ILs) as additives on the basis of in situ synchrotron radiation X-ray imaging. The phase contrast difference of real-time images indicates that zinc dendrites are preferentially developed on the substrate surface in the ammoniacal electrolytes. After adding imidazolium ILs, both nucleation overpotential and polarization extent increase in the order of additive-free < EMI-Cl < EMI-PF6< EMI-TFSA < EMI-DCA. The real-time X-ray images show that the EMI-Cl can suppress zinc dendrites, but result in the formation of the loose deposits. The EMI-PF6and EMI-TFSA additives can smooth the deposit morphology through suppressing the initiation and growth of dendritic zinc. The addition of EMI-DCA increases the number of dendrite initiation sites, whereas it decreases the growth rate of dendrites. Furthermore, the dissolution behaviors of zinc deposits are compared. The zinc dendrites show a slow dissolution process in the additive-free electrolyte, whereas zinc deposits are easily detached from the substrate in the presence of EMI-Cl, EMI-PF6, or EMI-TFSA due to the formation of the loose structure. Hence, the dependence of zinc dendrites on anions of imidazolium IL additives during both electrodeposition and dissolution processes has been elucidated. These results could provide the valuable information in perfecting the performance of zinc-based rechargeable batteries.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan 410083, China.
authors.forename: Yuexian
authors.initials: Y
authors.lastname: Song
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan 410083, China.
authors.forename: Jiugang
authors.initials: J
authors.lastname: Hu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan 410083, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Tang
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan 410083, China.
authors.forename: Wanmiao
authors.initials: W
authors.lastname: Gu
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan 410083, China.
authors.forename: Lili
authors.initials: L
authors.lastname: He
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University , Changsha, Hunan 410083, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Ji
keywords: dendritic suppression; imidazolium ionic liquids; in situ X-ray imaging; interfacial growth; zinc electrodeposition