Hydrothermal-Assisted Synthesis and Stability of Multifunctional MXene Nanobipyramids: Structural, Chemical, and Optical Evolution

Abstract

Recent advancements in two-dimensional materials have brought MXene (Ti3C2) into attention due to its exciting properties as a very promising material for various applications. In this work, we report a novel Ti3C2 nanobipyramid (Ti3C2 NB) structure obtained through a three-step process involving exfoliation, delamination, and subsequent hydrothermal treatment. The morphological and textural properties at each step of synthesis were studied using an array of experimental techniques such as transmission electron microscopy, scanning electron microscopy, and atomic force microscopy and the chemical properties through X-ray diffraction, Raman, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy analysis. The Ti3C2 NBs exhibit fluorescence with an excitation-dependent emission. Further, the effect of temperature and pH on the fluorescence was also investigated, which opens up its scope in bioanalytical applications. Ti3C2 NBs showed a ∼43% increase in photoluminescence intensity from pH 3 to 11 while a ∼38% increase with the temperature from 20 to 80 °C. Usually, MXenes are highly susceptible to oxidation, but the Ti3C2 NBs were found to be chemically and optically stable even after 30 days. Bestowed with good hydrophilicity, the material exhibited high biocompatibility on the mouse fibroblast cell line L929. Further, L929 cells also showed good cellular adhesion on a Ti3C2 NB-modified glass substrate. These properties pave a way for its multifunctional ability as a sensor for pH and temperature as well as bioimaging.

Influence of Surface States on the Optical and Cellular Property of Thermally Stable Red Emissive Graphitic Carbon Dots

“…They have easy proliferation and can be easily cultured in the laboratory. Therefore, these are utilized widely to investigate the preliminary toxicity of a biomaterial. , All the CDs showed excellent biocompatibility (more than 80% cell viability) even at very high concentrations (up to 250 μg/mL). SCD itself showed very high biocompatibility and the passivation did not show any effect to the cellular viability except FA_SCD.…”

Potential of MXene-Based Heterostructures for Energy Conversion and Storage

“…245 Moreover, the detailed characterization may provide insight into the structural evolution and stability of MXenes during the chemical reactions. 246…”

“…To this end, improving the operational stability of MXenes is still required for avoiding oxidation and hydrolysis . Moreover, the detailed characterization may provide insight into the structural evolution and stability of MXenes during the chemical reactions …”

Preclinical safety assessment of red emissive gold nanocluster conjugated crumpled MXene nanosheets: a dynamic duo for image-guided photothermal therapy

“…21 2D layered materials, such as chalcogenides, metal oxides, nitrides, sulphides, and carbides, have attracted a lot of attention as a result of progress in graphene research since its discovery. 22,23 MXenes are a group of two-dimensional (2D) transition-metal carbides and nitrides synthesized from the MAX phase where M is a transition metal (Ti, Ta, Nb, V, and Mo), A represents a group 13 or 14 element (Al, Si, Ge, Sn, S, As, P, In, Ga, Tl, and Pb) and X is C or N. The general chemical formula of MXenes is M n+1 X n T x (n = 1, 2, 3) where T x represents surface termination groups such as -OH, vO, and -F. [24][25][26] MXenes have shown considerable promise in a variety of fields, including energy, batteries, supercapacitors, photocatalysis, and environmental remediation. [27][28][29][30] Owing to their low cytotoxicity, unique optical properties, and easy bulk synthesis, MXene nanosheets are also gaining popularity in biological applications, 31 particularly in regenerative medicine, antibacterial and anticancer therapies, and bio-imaging, although they are still in early stages.…”