Synthesis of MXene/Ag Composites for Extraordinary Long Cycle Lifetime Lithium Storage at High Rates

Abstract

A new MXene/Ag composite was synthesized by direct reduction of a AgNO3 aqueous solution in the presence of MXene (Ti3C2(OH)0.8F1.2). The as-received MXene/Ag composite can be deemed as an excellent anode material for lithium-ion batteries, exhibiting an extraordinary long cycle lifetime with a large capacity at high charge-discharge rates. The results show that Ag self-reduction in MXene solution is related to the existence of low-valence Ti. Reversible capacities of 310 mAh·g(-1) at 1 C (theoretical value being ∼320 mAh·g(-1)), 260 mAh·g(-1) at 10 C, and 150 mAh·g(-1) at 50 C were achieved. Remarkably, the composite withstands more than 5000 cycles without capacity decay at 1-50 C. The main reasons for the long cycle life with high capacity are relevant to the reduced interface resistance and the occurrence of Ti(II) to Ti(III) during the cycle process.

Fabrication of tunable hierarchical MXene@AuNPs nanocomposites constructed by self-reduction reactions with enhanced catalytic performances

“…All chemicals were used, as received, without further purification. MXene (Ti 3 C 2 (OH x F 1-x ) 2 ) was synthesized according to previous reports [39,40].…”

“…Additionally, some special aspects regarding the catalytic performances of MXene materials, such as high-performance oxygen evolution, efficient electrocatalyst for hydrogen evolution and single-atom catalyst for CO oxidation, have been investigated [33][34][35][36][37]. Moreover, in recent years, our group has prepared some novel MXene/Ag composites, MXene-based nanoflower-shaped TiO 2 /C composites, and MXene/magnetic iron oxide nanocomposites, which demonstrate unusual electrocatalytic activity, extraordinary long cycle lifetime lithium storage and catalytic activity for the dehydrogenation of sodium alanates, respectively [38][39][40][41]. However, it is still challenging to design and obtain MXene-based composites via facile and effective self-assembly.…”

MXene‐Based Composites: Synthesis and Applications in Rechargeable Batteries and Supercapacitors

“…[187] Copyright 2016, Elsevier. [216] Copyright 2016 American Chemical Society. [188] Copyright 2017, Royal Society of Chemistry.…”

“…For example, Wang and coworkers modified a poly(o-phenylenediamine) (PoPD) with silver nanoparticles (Ag NPs) to form the PoPD/Ag composite as a glucose sensor material. By this method, metal NPs can be deposited on the surface of MXenes from their corresponding precursors, such as AgNO 3 , [216] HAuCl 4 , [59] PdCl 2 , [59] HPtCl 6 , [3] RuCl 3 , [217,218] NiCl 2 , [218] CoCl 2 , [3,217] etc. [214] Zhang et al used density functional theory (DFT) to explore the properties of a Ti/Ti 2 CO 2 composite, which shows better activity than precious metals in catalyzing CO oxidation.…”

“…The AgNO 3 precursor can be reduced into Ag NPs. [216] In addition to the 0D metal www.advmatinterfaces.de nanoparticles used to modify MXenes, metal nanowires have also been applied to improve the performance of MXene. [216] The mass percentage of Ag is from 5% to 15%, which results in the enlarging of the Ag NPs size from 10 to 100 nm.…”