Alkalized Ti3C2 MXene nanoribbons with expanded interlayer spacing for high-capacity sodium and potassium ion batteries. (October 2017) - Lian, Peichao
Abstract: As post-lithium ion batteries, both sodium ion batteries (SIBs) and potassium ion batteries (PIBs) possess great potential for large scale energy storage. However, the improvements of both SIBs and PIBs for practical applications are facing great challenges in the development of high-performance electrode materials. Here, we demonstrate the fabrication of alkalized Ti3 C2 (a-Ti3 C2 ) MXene nanoribbons attained by continuous shaking treatment of pristine Ti3 C2 MXene in aqueous KOH solution. Benefited from the expanded interlayer spacing of a-Ti3 C2, narrow widths of nanoribbons as well as three-dimensional interconnected porous frameworks for enhanced ion reaction kinetics and improved structure stability, the resulting a-Ti3 C2 anodes showed excellent sodium/potassium storage performance, for example, high reversible capacities of 168 and 136 mA h g −1 at 20 mA g −1 and 84 and 78 mA h g −1 at 200 mA g −1 were obtained for SIBs and PIBs, respectively. Notably, a-Ti3 C2 possessed outstanding long-term cyclability at high current density of 200 mA g −1, delivering a capacity of ~ 50 mA h g −1 for SIBs and ~ 42 mA h g −1 for PIBs after 500 cycles, which outperformed most of reported MXene based anodes for SIBs and PIBs. Moreover, this alkalization strategy could be extended as a universal approach for fabricating various alkalized MXene-based frameworks derived from a large family of MAX phases for numerous applications, such as catalysis, energy storage and conversion. Graphical abstract: Alkalized Ti3 C2 (a-Ti3 C2 ) MXene nanoribbons were successfully synthesized by shaking treatment of Ti3 C2 in KOH solution. Benefited from the expanded interlayer spacing, narrow widths of nanoribbons as well as 3D interconnected porous frameworks for enhanced ion reaction kinetics and improved structure stability, the resulting a-Ti3 C2 anodes showed excellent sodium/potassium storage performance. Highlights: Alkalized Ti3 C2 MXene nanoribbons (a-Ti3 C2 ) with expanded interlayer spacing is synthesized by shaking treatment of Ti3 C2 MXene in KOH solution. a-Ti3 C2 shows narrow widths of nanoribbons (6–22 nm) as well as 3D interconnected porous frameworks. a-Ti3 C2 displays high capacities and superior cycling stability over 500 cycles for sodium/ potassium storage.