A two-dimensional assembly of ultrafine cobalt oxide nanocrystallites anchored on single-layer Ti3C2Tx nanosheets with enhanced lithium storage for Li-ion batteries. Issue 36 (19th July 2019)

• Record Type: Journal Article
• Authors: Sun, Xuan; Tan, Ke; Liu, Yang; Zhang, Jinyang; Denis, Dienguila Kionga; Zaman, Fakhr uz; Hou, Linrui; Yuan, Changzhou
• Is Part Of: Nanoscale. Volume 11:Issue 36(2019)
• Page Start: 16755
• Page End: 16766
• Publication Date: 2019-07-19
• Subjects: Nanoscience -- Periodicals; Nanotechnology -- Periodicals; 620.505
• DOI: 10.1039/c9nr04377b
• Languages: English
• ISSNs: 2040-3364

Abstract

Abstract : A two-dimensional assembly of ultrafine Co3 O4 nanocrystallites anchored on single-layer Ti3 C2 T x nanosheets was smartly synthesized, and it exhibited superior lithium storage properties as competitive anodes for Li-ion batteries. Abstract : Recently, Ti-based MXenes were expected to compete with graphene and other carbonaceous materials towards Li-ion batteries (LIBs) due to their two-dimensional (2D) open structure, cost efficiency, superior conductivity and low Li + diffusion barrier. However, the relatively moderate capacity and aggregation tendency hamper their practical applications in next-generation LIBs. Herein, we explore for the first time a scalable bottom-up approach to fabricate a series of Co3 O4 @single-layer Ti3 C2 T x (s-Ti3 C2 T x ) hybrids, where numerous homogeneous Co3 O4 nanocrystallites (NCs), serving both as a spacer and electroactive phase, are anchored uniformly on the surface of s-Ti3 C2 T x nanosheets (NSs) through the Co–O–Ti interfacial bonds. Furthermore, detailed experimental analyses clearly shed light upon the formation mechanism of the hybrid Co3 O4 @s-Ti3 C2 T x NSs. Thanks to the structural and compositional merits, the 2D Co3 O4 @s-Ti3 C2 T x NSs even exhibit a remarkable high-rate capacity of ∼223 mA h g −1 at an ultra-high current density of 10 A g −1, and a long-span cycle life with a high reversible capacity of 550 mA h g −1 at 1 A g −1 after 700 consecutive cycles. Corresponding density functional theory calculation further confirms that the Co–O–Ti interfacial function leads to an even higher pseudocapacitive contribution and faster lithium storage behavior due to the enhanced interfacial electron transfer.