Early Transition Metal Nitrides Research Articles

Molten Salt Derived MXenes: Synthesis and Applications.

About one decade after the first report on MXenes, these 2D early transition metal carbides or nitrides have become among the best-performing materials in electrode applications related to electrical energy storage devices and power-to-fuels conversion. MXenes are obtained by a top-down approach starting from the appropriate 3D MAX phase that undergoes etching of the A-site metal. Initial etching procedures are based on the use of concentrated HF or the in situ generation of this highly corrosive and poisonous reagent. Etching of the MAX phase is one of the major hurdles limiting the progress of the field. The present review summarizes an alternative, universal, and easily scalable etching procedure based on treating the MAX precursor with a Lewis acid molten salt. The review starts with presenting the current state of the art of the molten salt etching procedure to obtain or modify MXene, followed by a summary of the applications of these MXene samples. The aim of the review is to show the versatility and advantages of molten salt etching in terms of general applicability, control of the surface terminal groups, and uniform deposition of metal nanoparticles, among other features of the procedure.

Environmentally stable nanoscale superlubricity of multi-layered Ti3C2Tx MXene

With their two-dimensional layered structure, excellent mechanical behavior, and reduced interlayer sliding resistance, early transition metal carbides and nitrides (MXenes) have demonstrated promising solid lubrication properties at the macro- and nanoscale. Although MXenes can exist in several morphologies (multi-layer particles, clay, or single-to-few layer flake dispersions), the dependence of friction on the number of MXene layers is still yet to be fully understood. Here, we present number-of-layer-dependent friction property of single-to-four layer flakes of Ti3C2Tx MXene, produced using a modified MAX synthesis method, via atomic force microscopy with diamond-like-carbon and silicon probes at the nanoscale on silicon substrates. We demonstrate the superlubricity of single-layer Ti3C2Tx MXene as well as the effect of layers of Ti3C2Tx in an inert nitrogen atmosphere (coefficient of friction as low as 0.0039 ± 0.0006 for a bi-layer). Furthermore, we present the long-term stability of Ti3C2Tx's superlubricity up to a month in ambient conditions and up to three months in a vacuum environment. We believe that this investigation of layer-dependent and long-lasting MXene superlubricity at the nanoscale illustrates the potential of implementation of MXene into both space and industrial applications.

Valence electron concentration- and N vacancy-induced elasticity in cubic early transition metal nitrides

Motivated by frequently reported deviations from stoichiometry in cubic transition metal nitride (TMNx) thin films, the effect of N-vacancy concentration on the elastic properties of cubic TiNx, ZrNx, VNx, NbNx, and MoNx (0.72≤x≤1.00) is systematically studied by density functional theory (DFT) calculations. The predictions are validated experimentally for VNx (0.77≤x≤0.97). The DFT results indicate that the elastic behavior of the TMNx depends on both the N-vacancy concentration and the valence electron concentration (VEC) of the transition metal: While TiNx and ZrNx exhibit vacancy-induced reductions in elastic modulus, VNx and NbNx show an increase. These trends can be rationalized by considering vacancy-induced changes in elastic anisotropy and bonding. While introduction of N-vacancies in TiNx results in a significant reduction of elastic modulus along all directions and a lower average bond strength of Ti–N, the vacancy-induced reduction in [001] direction of VNx is overcompensated by the higher stiffness along [011] and [111] directions, resulting in a higher average bond strength of V–N. To validate the predicted vacancy-induced changes in elasticity experimentally, close-to-single-crystal VNx (0.77≤x≤0.97) are grown on MgO(001) substrates. As the N-content is reduced, the relaxed lattice parameter a0, as probed by X-ray diffraction, decreases from 4.128 Å to 4.096 Å. This reduction in lattice parameter is accompanied by an anomalous 11% increase in elastic modulus, as determined by nanoindentation. As the experimental data agree with the predictions, the elasticity enhancement in VNx upon N-vacancy formation can be understood based on the concomitant changes in elastic anisotropy and bonding.

Recent Advances in Two-Dimensional MXene-Based Electrochemical Biosensors for Sweat Analysis.

Sweat, a biofluid secreted naturally from the eccrine glands of the human body, is rich in several electrolytes, metabolites, biomolecules, and even xenobiotics that enter the body through other means. Recent studies indicate a high correlation between the analytes' concentrations in the sweat and the blood, opening up sweat as a medium for disease diagnosis and other general health monitoring applications. However, low concentration of analytes in sweat is a significant limitation, requiring high-performing sensors for this application. Electrochemical sensors, due to their high sensitivity, low cost, and miniaturization, play a crucial role in realizing the potential of sweat as a key sensing medium. MXenes, recently developed anisotropic two-dimensional atomic-layered nanomaterials composed of early transition metal carbides or nitrides, are currently being explored as a material of choice for electrochemical sensors. Their large surface area, tunable electrical properties, excellent mechanical strength, good dispersibility, and biocompatibility make them attractive for bio-electrochemical sensing platforms. This review presents the recent progress made in MXene-based bio-electrochemical sensors such as wearable, implantable, and microfluidic sensors and their applications in disease diagnosis and developing point-of-care sensing platforms. Finally, the paper discusses the challenges and limitations of MXenes as a material of choice in bio-electrochemical sensors and future perspectives on this exciting material for sweat-sensing applications.

Additively manufactured MAX- and MXene-composite scaffolds for bone regeneration- recent advances and future perspectives

Human bones can suffer from various injuries, such as fractures, bone cancer, among others, which has initiated research activities towards bone replacement using advanced bio-materials. However, it is still challenging to design bio-scaffolds with bone-inducing agents to regenerate bone defects. In this regard, MAX-phases and MXenes (early transition metal carbides and/or nitrides) have gained notable attention due to their unique hydrophilicity, bio-compatibility, chemical stability, and photothermal properties. They can be used in bone tissue engineering as a suitable replacement or reinforcement for common bio-materials (polymers, bio-glasses, metals, or hydroxyapatite). To fabricate bio-scaffolds, additive manufacturing is prospective due to the possibility of controlling porosity and creating complex shapes with high resolution. Until now, no comprehensive article summarizing the existing state-of-the-art related to bone scaffolds reinforced by MAX-phases and MXenes fabricated by additive manufacturing has been published. Therefore, our article addresses the reasons for using bone scaffolds and the importance of choosing the most suitable material. We critically discuss the recent developments in bone tissue engineering and regenerative medicine using MAX-phases and MXenes with a particular emphasis on manufacturing, mechanical properties, and bio-compatibility. Finally, we discuss the existing challenges and bottlenecks of bio-scaffolds reinforced by MAX-phases and MXenes before deriving their future potential.

Interfacial interactions of doped-Ti3C2 MXene/MAPbI3 heterostructures: surfaces and the theoretical approach.

The work function (WF) of perovskite materials is essential for developing optoelectronic devices enabling efficient charge transfer at their interfaces. Perovskite's WF can be tuned by MXenes, a new class of two-dimensional (2D) early transition metal carbides, nitrides, and carbonitrides. Their variable surface terminations or the possibility of introducing elemental dopants could advance perovskites. However, the influence of doped-MXenes on perovskite materials is still not fully understood and elaborated. This study provides mechanistic insight into verifying the tunability of MAPbI3 WF by hybridizing with fluorine-terminated Ti3C2Tx (F-MXene) and nitrogen-doped Ti3C2Tx (N-MXene). We first reveal the interfacial interaction between MAPbI3 and MXenes via X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and photoluminescence spectroscopy (PL). UPS supported by density functional theory (DFT) calculations allowed the description of the influence of F and N on MXene's WF. Furthermore, we developed MAPbI3/MXene heterostructures using F- and N-MXenes. The F-MXenes extended the most WF of MAPbI3 from 4.50 eV up to 3.00 eV, compared to only a small shift for N-MXene. The underlying mechanism was charge transfer from low WF F-MXene to MAPbI3, as demonstrated by PL quenching in MAPbI3/F-MXene heterostructures. Altogether, this work showcases the potential of fluorine-doped MXenes over nitrogen-doped MXenes in advancing perovskite heterostructures, thus opening a door for efficient optoelectronic devices.

Perspectives of 2D MXene Tribology.

The large and rapidly growing family of 2D early transition metal carbides, nitrides, and carbonitrides (MXenes) raises significant interest in the materials science and chemistry of materials communities. Discovered a little more than a decade ago, MXenes have already demonstrated outstanding potential in various applications ranging from energy storage to biology and medicine. The past two years have witnessed increased experimental and theoretical efforts toward studying MXenes' mechanical and tribological properties when used as lubricant additives, reinforcement phases in composites, or solid lubricant coatings. Although research on the understanding of the friction and wear performance of MXenes under dry and lubricated conditions is still in its early stages, it has experienced rapid growth due to the excellent mechanical properties and chemical reactivities offered by MXenes that make them adaptable to being combined with other materials, thus boosting their tribological performance. In this perspective, the most promising results in the area of MXene tribology are summarized, future important problems to be pursued further are outlined, and methodological recommendationsthat could be useful for experts as well as newcomers to MXenes research, in particular, to the emerging area of MXene tribology, are provided.

CO oxidation on MXene (Mo2CS2) supported single-atom catalyst: A termolecular Eley-Rideal mechanism

Finding transition metal catalysts for effective catalytic conversion of CO to CO2 has attracted much attention. MXene as a new 2D layered material of early transition metal carbides, nitrides, and carbo-nitrides is a robust support for achoring metal atoms. In this study, the electronic structure, geometries, thermodynamic stability, and catalytic activity of MXene (Mo2CS2) supported single noble metal atoms (NM = Ru, Rh, Pd, Ir, Pt and Au) have been systematically examined using first-principles calculations and ab initio molecular dynamic (AIMD) simulations. First, AIMD simulations and phonon spectra demonstrate the dynamic and thermal stabilities of Mo2CS2 monolayer. Three likely reaction pathways, Langmuir-Hinshelwood (LH), Eley-Rideal (ER), and Termolecular Eley–Rideal (TER) for CO oxidation on the Ru1- and Ir1@Mo2CS2 SACs, have been studied in detail. It is found that CO oxidation mainly proceeds via the TER mechanism under mild reaction conditions. The corresponding rate-determining steps are the dissociation of the intermediate (OCO-Ru1-OCO) and formation of OCO-Ir1-OCO intermediate. The downshift d-band center of Ru1- and Ir1@Mo2CS2 help to enhance activity and improve catalytst stability. Moreover, a microkinetic study predicts a maximum CO oxidation rate of 4.01 × 102 s-1 and 4.15 × 103 s-1 (298.15 K) following the TER pathway for the Ru1- and Ir1@Mo2CS2 catalysts, respectively. This work provides guideline for fabricating and designing highly efficient SACs with superb catalyts using MXene materials.

Detailed study of reactively sputtered ScN thin films at room temperature

To contemplate an alternative approach for the minimization of diffusion at high temperature, present findings impart viability of room-temperature deposited reactively sputtered ScN thin films. The adopted route endows precise control over the RN2 flow for a methodical structural phase evolution from Sc→ScN and probe the correlated physical aspects of the highly textured ScN samples. In the nitrided regime i.e. at RN2 = 2.5–100% flow, incorporation of unintentional oxygen defects was evidenced from surface sensitive soft x-ray absorption spectroscopy study, though less compared to their metal (RN2 = 0%) and interstitial (RN2 = 1.6%) counterparts, due to higher Gibbs free energy for Sc-O-N formation with no trace of ligand field splitting around the O K-edge spectra. To eradicate the skepticism of appearance of N K-edge (401.6 eV) and Sc L-edge (402.2 eV) absorption spectra adjacent to each other, the first-ever Sc K-edge study has been adopted to validate complementary insight on the metrical parameters of the Sc-N system. Optical bandgaps of the polycrystalline ScN thin film samples were found to vary between 2.25 and 2.62 eV as obtained from the UV–vis spectroscopy, whereas, the nano-indentation hardness and modulus of the as-deposited samples lie between 15–34 GPa and 152–476 GPa, respectively following a linearly increasing trend of resistance to plastic deformations with an exception at 34 GPa in case of RN2 = 5% sample. Besides, contrary to other early 3d transition metal nitrides (TiN, VN, CrN), a comprehensive comparison of noticeably large homogeneity range in Sc-N has been outlined to apprehend the minuscule lattice expansion over the large RN2 realm.

Electrochemical biosensors based on Ti3C2Tx MXene: future perspectives for on-site analysis

MXenes are recently developed two-dimensional layered materials composed of early transition metal carbides and/or nitrides that provide unique characteristics for biosensor applications. This review presents the recent progress made on the usage and applications of MXenes in the field of electrochemical biosensors, including microfluidic biosensors and wearable microfluidic biosensors, and highlights the challenges with possible solutions and future needs. The multilayered configuration and high conductivity make these materials as an immobilization matrix for the biomolecule immobilization with activity retention and to be explored in the fabrication of electrochemical sensors, respectively. First, how the MXene nanocomposite as an electrode modifier affects the sensing performance of the electrochemical biosensors based on enzymes, aptamer/DNA, and immunoassays is well described. Second, recent developments in MXene nanocomposites as wearable biosensing platforms for the biomolecule detection are highlighted. This review pointed out the future concerns and directions for the use of MXene nanocomposites to fabricate advanced electrochemical biosensors with high sensitivity and selectivity. Specifically, possibilities for developing microfluidic electrochemical sensors and wearable electrochemical microfluidic sensors with integrated biomolecule detection are emphasized.

Unveiling the Interfacial and Structural Heterogeneity of Ti3C2Tx MXene Etched with CoF2/HCl by Integrated in Situ Thermal Analysis.

Ti3C2Tx MXene is a member of the recently discovered two-dimensional early transition metal carbide and nitride family of MXenes with potential applications in energy storage and heterogeneous catalysis at elevated temperatures. Here, we apply a suite of in situ techniques to probe Ti3C2Tx MXene's thermal evolutions, including in situ X-ray diffraction (XRD), in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), and integrated thermogravimetry-differential scanning calorimetry-mass spectrometry (TG-DSC-MS). In light of this set of in situ investigations, we find heterogeneity in the layering of Ti3C2Tx MXene revealed only at higher temperatures. Our findings present behavior up to 600 °C, particularly interlayer water and -OH surface end-capping groups. In one group of layers, their interlayer spacing shrinks as water deintercalates, but the other group of layers unexpectedly shows no change in the interlayer spacing. This is strong evidence that intercalants act as guest pillaring agents in the latter layering group, which stabilize these layers at higher temperatures while keeping the interlayer space accessible.

(Invited) Photoelectrochemical Behavior of Transition Metal Alloyed Nitride MXenes

Two-dimensional (2D) MXenes based on early transition metal carbides and nitrides have highly tunable electrochemical properties including excellent catalytic activity for solar fuels generation. These properties can be manipulated by modifying the basal plane chemistry. In this presentation, we will describe our recent development of mixed transition metal nitride MXenes, M-Ti4N3Tx (M = V, Cr, Mo, or Mn; Tx = O and/or OH), by modifying pristine exfoliated Ti4N3Tx MXene with V, Cr, Mo, and Mn salts using a simple solution-based method. We will show that the transition metal alloying process induces highly tunable hydrogen evolution reaction (HER) electrocatalytic activity in 0.5 M H2SO4 electrolyte as follows: V-Ti4N3Tx > Cr-Ti4N3Tx > Mo-Ti4N3Tx > Mn-Ti4N3Tx > pristine Ti4N3Tx with overpotentials as low as 330 mV at –10 mA cm–2. We further characterize these M-Ti4N3Tx MXenes using scanning electrochemical microscopy (SECM) to demonstrate that catalytic activity occurs on the basal plane, and additionally show that these MXenes exhibit semiconducting behavior. Lastly, we use in situ X-ray absorption spectroelectrochemistry to probe the transition metal oxidation states and unveil the mechanism of HER electrocatalysis.

Applications of Two Dimensional Material-MXene for Proton Exchange Membrane Fuel Cells (PEMFCs) and Water Electrolysis

Abstract: A new kind of two-dimensional (2D) material MXene (early transition metal carbides, nitrides and carbonitrides) is obtained by selective etching the A element from the MAX phases. MXene exhibits both the metallic conductivity and the hydrophilic nature due to its metal layer structure and hydroxyl or oxygen terminated surfaces. This review provides an overview of the MXene used in the electrolytes and electrodes for the fuel cells and water splitting. MXene with functional groups termination could construct ion channels that significantly benefit ion conductivity through the electrolyte. The metal supported by MXene interaction offers electronic, compositional, and geometric effects that could enhance the catalytic activity and stability. MXene has already shown promising performance for fuel cells and water electrolysis. Herein, the etching and intercalation methods of MXene in recent years are summarized. The applications of MXene for fuel cells electrolyte, catalyst and water splitting catalyst are revealed to provide a more brief idea for MXene used as new energy materials.

Achieving superlubricity with 2D transition metal carbides (MXenes) and MXene/graphene coatings

Two-dimensional (2D) materials have demonstrated unique friction and antiwear properties unmatched by their bulk (3D) counterparts. A relatively new, large and quickly growing family of two-dimensional early transition metal carbides and nitrides (MXenes) present a great potential in different applications. There is a growing interest in understanding the mechanical and tribological properties of MXenes, however, no report of MXene superlubricity in a solid lubrication process at the macroscale has been presented. Here we investigate the tribological properties of two-dimensional titanium carbide (Ti3C2) MXene deposited on SiO2-coated silicon (Si) substrates subjected to wear by sliding against a diamond-like carbon (DLC)-coated steel ball counterbody using a ball-on-disc tribometer. We have observed that a reduction of the friction coefficient to the superlubric regime (0.0067 ± 0.0017) can be achieved with Ti3C2 MXene in dry nitrogen environment. Moreover, the addition of graphene to Ti3C2 further reduced the friction by 37.3% and wear by the factor of 2 as compared to Ti3C2 alone, while the superlubricity behavior of the MXene remains unchanged. These results open up new possibilities for exploring the family of MXenes in various tribological applications.

Adhesion Between MXenes and Other 2D Materials.

MXenes, a large family of two-dimensional (2D) early transition metal carbides and nitrides, have excellent electrical and electrochemical properties, which can also be explored in assemblies with other 2D materials, like graphene and transition metal dichalcogenides (TMDs), creating heterostructures with unique properties. Understanding the interaction mechanism between 2D materials is critical for the design and manipulation of these 2D heterostructures. Our previous work investigated the interaction between SiO2 and two MXenes (Ti3C2Tx and Ti2CTx). However, no experimental research has been done on MXene interlayer interactions and interactions in MXene heterostructures. Here, we used atomic force microscopy (AFM) with SiO2 tip and Ti3C2Tx and Ti2CTx MXene-coated tips, respectively, to measure the adhesion energies of graphene, MoSe2, Ti3C2Tx, and Ti2CTx MXene with other 2D materials. The measured adhesion energies show that only the interfaces involving graphene demonstrate dependence on the number of material monolayers in a stack. Comparing 40 interacting pairs of 2D materials, the lowest adhesion energy (∼0.27 J/m2) was found for the interfaces involving MoSe2 and the highest adhesion energy was observed for the interfaces involving Ti3C2Tx (∼1.23 J/m2). The obtained set of experimental data for 2D interfaces involving MXenes provides a basis for a future in-depth understanding of adhesive mechanisms at interfaces between 2D materials, which is an important topic for the design of 2D heterostructures with controlled interfacial strength and properties.

Non-noble metal single-atom catalyst of Co1/MXene (Mo2CS2) for CO oxidation

MXene is a variety of new two-dimensional (2D) materials with early transition metal carbides, nitrides, and carbonitrides. Quantum chemical studies have been carried out on the geometries, electronic structures, stability and catalytic properties of a non-noble metal single-atom catalyst (SAC) with single Co atom anchored on MXene materials of Mo2CS2. The Co adatom anchored on top of the Mo atom of this MXene is found to be rather stable, and this SAC is appropriate for CO oxidation. The charge transfers from the surface to the adsorbed CO and O2 play a significant role in the activation of these molecules on Co1/Mo2CS2. With this catalyst, the Eley-Rideal (ER), Langmuir-Hinshelwood (LH), and Termolecular Eley-Rideal (TER) mechanisms are explored for CO oxidation. We find that, while all the three mechanisms are feasible at low temperature, Co1/Mo2CS2 possesses higher catalytic activity for CO oxidation through the TER mechanism that features an intriguing OC(OO)CO intermediate (IM) adsorbed on Co single atom. The calculated activation energy barriers of the rate-limiting step are 0.67 eV (TER), 0.78 eV (LH) and 0.88 eV (ER), respectively. The present study illustrates that it is promising to develop and design low-cost, non-noble metal SACs using MXene types of 2D materials.

Bioactive and trackable MXene quantum dots for subcellular nanomedicine applications

Next-generation “early transition metal carbides and nitrides” (MXene) materials have facile and economic processing with simultaneous synthesis and functionalization. Their surface characteristics can be tailored for specific applications, including energy storage, sensors, and water filtration, by adjusting synthetic parameters. Furthermore, MXene possesses excellent biocompatibility and can be designed for anticancer, antibacterial, and immunomodulatory properties. However, a major limitation facing systemic delivery of nanoparticles is ensuring successful uptake from the bloodstream into the desired site of action. An important consideration is the vascular endothelial cell (EC), which serves as the barrier between blood and organs. Therefore, cellular uptake of engineered nanoparticles by EC is important to advance their use in nanomedicine. In this study, smart zero-dimensional biocompatible titanium carbide (Ti3C2Tx) MXene quantum dots (MQD) were synthesized with specific surface modifications for subcellular nanomedicine applications. MQD were shown to be spontaneously uptaken into human ECs within 24 h of cell culture. MQD localization was observed to be highly stable during this with no significant changes seen in cell morphology. Furthermore, uptaken MQD maintained their strong autofluorescence properties at different excitation-emission wavelengths to enable post-delivery monitoring and tracking. This novel finding represents promising progress in the application of MQD for nanomedicine.

Generation of Fuel and Value-Added Chemicals from Carbon Dioxide (CO2)

Despite its life-threatening long term effects, the continuous increase of carbon dioxide (CO2) in the environment requires immediate actions to control the accelerating climate change. An appealing solution to this problem is to utilize CO2 as feedstock to generate useful chemicals, e.g., fuel, hydrocarbons, and valuable chemicals. The chemical inertness of CO2 needs considerably large energy for its conversion into useful chemicals. Therefore, CO2 reduction reaction requires an effective catalyst for its conversion into fuel (methanol, methane) and industrial chemicals (syngas, formic acid). Recently, two-dimensional layers of early transition metal carbides and nitrides, called MXene, have shown potential for catalysis due to its exposed transition metal sites, and mechanical and chemical stability at high temperatures. Herein, the author presents the MXene as a potential heterogeneous catalyst for the CO2 reduction reaction (CRR), and the future scope in this currently developing field.

Basal Plane Hydrogen Evolution Activity from Mixed Metal Nitride MXenes Measured by Scanning Electrochemical Microscopy

Abstract2D early transition metal carbide and nitride MXenes have intriguing properties for electrochemical energy storage and electrocatalysis. These properties can be manipulated by modifying the basal plane chemistry. Here, mixed transition metal nitride MXenes, M‐Ti4N3Tx (M = V, Cr, Mo, or Mn; Tx = O and/or OH), are developed by modifying pristine exfoliated Ti4N3Tx MXene with V, Cr, Mo, and Mn salts using a simple solution‐based method. The resulting mixed transition metal nitride MXenes contain 6–51% metal loading (cf. Ti) that exhibit rich electrochemistry including highly tunable hydrogen evolution reaction (HER) electrocatalytic activity in a 0.5 m H2SO4 electrolyte as follows: V‐Ti4N3Tx > Cr‐Ti4N3Tx > Mo‐Ti4N3Tx > Mn‐Ti4N3Tx > pristine Ti4N3Tx with overpotentials as low as 330 mV at −10 mA cm−2 with a charge‐transfer resistance of 70 Ω. Scanning electrochemical microscopy (SECM) reveals the electrochemical activity of individual MXene flakes. The SECM data corroborate the bulk HER activity trend for M‐Ti4N3Tx as well as provide the first experimental evidence that HER results from catalysis on the MXene basal plane. These electrocatalytic results demonstrate a new pathway to tune the electrochemical properties of MXenes for water splitting and related electrochemical applications.

Synthesis, plasmonic properties, and CWA simulant decontamination activity of first row early transition metal nitride powders and nanomaterials

The complexes MCl3(THF)3 (M = Ti, V, Cr) were used as precursors to form early transition metal nitrides, and solid solutions of these isomorphous complexes MxM’1−xCl3(THF)3 were prepared by co-crystallization. Heating the precursor under NH3 flow from 800 to 950 °C produced powders of the nitride MN, and solid solutions of these precursors produced alloys of the nitrides. Nanomaterials were synthesized by two methods: (1) reaction of a MCl3(THF)3 solution with 3 eq of KNH2 in THF in the presence (or absence) of oleylamine, followed by nitridation under NH3 flow at 650–950 °C and (2) loading a porous catalyst support such as pelletized Al2O3 with the MCl3(THF)3 complex, followed by similar heat treatment. The materials were characterized by powder X-ray diffraction, elemental analysis, SEM, and optical spectroscopy. Diffuse reflectance and UV–Vis-NIR spectroscopy showed the local surface plasmonic resonances (LSPRs). Although diffuse reflectance and UV–Vis-NIR spectroscopy showed LSPRs whose position was sensitive to surface functionalization and conditions of preparation, preliminary results show TiN nanoparticles have some activity in the degradation of the Chemical Warfare Agent (CWA) simulant DEMETON-S, but light plays no role in the mechanism.