Details

Autor(en) / Beteiligte

• Tang, Yuxin
• Zhang, Yanyan
• Malyi, Oleksandr I.
• Bucher, Nicolas
• Xia, Huarong
• Xi, Shibo
• Zhu, Zhiqiang
• Lv, Zhisheng
• Li, Wenlong
• Wei, Jiaqi
• Srinivasan, Madhavi
• Borgna, Armando
• Antonietti, Markus
• Du, Yonghua
• Chen, Xiaodong

Titel

Identifying the Origin and Contribution of Surface Storage in TiO2(B) Nanotube Electrode by In Situ Dynamic Valence State Monitoring

Ist Teil von

• Advanced materials (Weinheim), 2018-08, Vol.30 (33), p.e1802200-n/a

Ort / Verlag

Weinheim: Wiley Subscription Services, Inc

Erscheinungsjahr

2018

Quelle

Wiley Online Library - AutoHoldings Journals

Beschreibungen/Notizen

• Fundamental insight into the surface charging mechanism of TiO2(B) nanomaterials is limited due to the complicated nature of lithiation behavior, as well as the limitations of available characterization tools that can directly probe surface charging process. Here, an in situ approach is reported to monitor the dynamic valence state of TiO2(B) nanotube electrodes, which utilizes in situ X‐ray absorption spectroscopy (XAS) to identify the origin and contribution of surface storage. A real‐time correlation is elucidated between the rate‐dependent electrode performance and dynamic Ti valence‐state change. A continuous Ti valence state change is directly observed through the whole charging/discharging process regardless of charging rates, which proves that along with the well‐known non‐faradaic reaction, the surface charging process also originates from a faradaic reaction. The quantification of these two surface storage contributions at different charging rates is further realized through in situ dynamic valence state monitoring combined with traditional cyclic voltammetry measurement. The methodology reported here can also be applied to other electrode materials for the real‐time probing of valence state change during electrochemical reactions, the quantification of the faradaic and non‐faradaic reactions, and the eventual elucidation of electrochemical surface charging mechanisms. The origin and contribution of surface storage in a prototype TiO2(B) nanotube electrode by an in situ dynamic valence state monitoring approach are identified. Benefited from this, non‐faradaic and faradaic capacity from the surface reaction are identified and quantified in conjunction with a cyclic voltammetry measurement, putting an end to the long‐time question on surface reaction over distinguishing its non‐faradaic and faradaic contributions.