Deformation of and Interfacial Stress Transfer in TiC MXene-Polymer Composites.

Transitional metal carbides and nitrides (MXenes) have promise for incorporation into multifunctional composites due to their high electrical conductivity and excellent mechanical and tribological properties. It is unclear, however, to what extent MXenes are also able to improve the mechanical properties of the composites and, if so, what would be the optimal flake size and morphology. Herein, TiCT MXene is demonstrated to be indeed a good candidate for mechanical reinforcement in polymer matrices.

Modified MAX Phase Synthesis for Environmentally Stable and Highly Conductive TiC MXene.

One of the primary factors limiting further research and commercial use of the two-dimensional (2D) titanium carbide MXene TiC, as well as MXenes in general, is the rate at which freshly made samples oxidize and degrade when stored as aqueous suspensions. Here, we show that including excess aluminum during synthesis of the TiAlC MAX phase precursor leads to TiAlC grains with improved crystallinity and carbon stoichiometry (termed Al-TiAlC). MXene nanosheets (Al-TiC) produced from this precursor are of higher quality, as evidenced by their increased resistance to oxidation and an increase in their electronic conductivity up to 20 000 S/cm.

Tailoring Electronic and Optical Properties of MXenes through Forming Solid Solutions.

Alloying is a long-established strategy to tailor properties of metals for specific applications, thus retaining or enhancing the principal elemental characteristics while offering additional functionality from the added elements. We propose a similar approach to the control of properties of two-dimensional transition metal carbides known as MXenes. MXenes (MX) have two sites for compositional variation: elemental substitution on both the metal (M) and carbon/nitrogen (X) sites presents promising routes for tailoring the chemical, optical, electronic, or mechanical properties of MXenes.

Tunable electrochromic behavior of titanium-based MXenes.

Two-dimensional transition metal carbides, nitrides and carbonitrides, popular by the name MXenes, are a promising class of materials as they exhibit intriguing optical, optoelectronic and electrochemical properties. Taking advantage of their metallic conductivity and hydrophilicity, titanium carbide MXenes (Ti3C2Tx and others) are used to fabricate solution processable transparent conducting electrodes (TCEs) for the design of three-electrode electrochromic cells. However, the tunable electrochromic behavior of various titanium-based MXene compositions across the entire visible spectrum has not yet been demonstrated.

Synthesis of MoVAlC MAX Phase and Two-Dimensional MoVC MXene with Five Atomic Layers of Transition Metals.

MXenes are a family of two-dimensional (2D) transition metal carbides, nitrides, and carbonitrides with a general formula of MXT, in which two, three, or four atomic layers of a transition metal (M: Ti, Nb, V, Cr, Mo, Ta, etc.) are interleaved with layers of C and/or N (shown as X), and T represents surface termination groups such as -OH, ═O, and -F. Here, we report the scalable synthesis and characterization of a MXene with five atomic layers of transition metals (MoVCT), by synthesizing its MoVAlC MAX phase precursor that contains no other MAX phase impurities.

Tuning the Electrochemical Performance of Titanium Carbide MXene by Controllable In Situ Anodic Oxidation.

MXenes are a class of two-dimensional (2D) transition metal carbides, nitrides and carbonitrides that have shown promise for high-rate pseudocapacitive energy storage. However, the effects that irreversible oxidation have on the surface chemistry and electrochemical properties of MXenes are still not understood. Here we report on a controlled anodic oxidation method which improves the rate performance of titanium carbide MXene (Ti C T T refers to -F, =O, -Cl and -OH) electrodes in acidic electrolytes.

Automated Scalpel Patterning of Solution Processed Thin Films for Fabrication of Transparent MXene Microsupercapacitors.

A simple and generic strategy is proposed to pattern thin films deposited by a solution processable route. A soft approach based on an automated scalpel technique is developed to engrave thin films in a single step for sculpting functional planar devices. MXenes-the emerging family of 2D transition metal carbides and nitrides-combine metallic conductivity and hydrophilicity, enabling solution processing of transparent conducting electrodes (TCEs) under ambient conditions.

2D titanium carbide (MXene) for wireless communication.

With the development of the Internet of Things (IoT), the demand for thin and wearable electronic devices is growing quickly. The essential part of the IoT is communication between devices, which requires radio-frequency (RF) antennas. Metals are widely used for antennas; however, their bulkiness limits the fabrication of thin, lightweight, and flexible antennas.

Selective Etching of Silicon from Ti SiC (MAX) To Obtain 2D Titanium Carbide (MXene).

Until now, MXenes could only be produced from MAX phases containing aluminum, such as Ti AlC . Here, we report on the synthesis of Ti C (MXene) through selective etching of silicon from titanium silicon carbide-the most common MAX phase. Liters of colloidal solutions of delaminated Ti SiC -derived MXene (0.