Michael Naguib

• PhD
• Professor (Associate) at Tulane University

We use Raman spectroscopy to study the substrate effect from Ti 3 C 2 MXene on the lattice vibrational modes in MoS 2 . We observed redshifts from the fingerprint peaks in MoS 2 , and explained...

The increasing reliance on nuclear energy as a significant low‐carbon power source necessitates effective solutions for managing radioactive emissions. This study introduces a novel application of MXene nanohybrids, specifically silver‐MXene (Ag‐Ti3C2Tx), as an effective sorbent for radioiodine off‐gas capture at an operating temperature of 150 °C....

Two-dimensional van der Waals heterostructures with exotic quantum phenomena have garnered a huge surge in the field of optoelectronic devices. Herein, we report spectroscopic evidence of efficient interfacial charge transfers at the interface of novel 2D/2D V4C3Tx MXene/protonated g-C3N4 (PCN) heterostructured thin film, demonstrating robust photo...

MBenes, a novel class of transition metal borides, represents an exciting advancement in two-dimensional (2D) materials. This study introduces a novel and mild microwave-assisted hydrothermal method. The multilayered (ML) MoAlB@MBene...

Two-dimensional (2D) transition metal carbides and nitrides, known as MXenes, possess unique physical and chemical properties, enabling diverse applications in fields ranging from energy storage to communication, catalysis, sensing, healthcare, and beyond. The transition metal and nonmetallic atoms in MXenes can exhibit distinct coordination enviro...

Herein, we report the synthesis of two-dimensional Ta2Se2C (2D-Ta2Se2C) nanosheets using electrochemical lithiation in multilayer Ta2Se2C followed by sonication in deionized water. Multilayer Ta2Se2C was obtained via solid-state synthesis of FexTa2Se2C followed by chemical etching of Fe. 2D-Ta2Se2C exhibited promising electrocatalytic activity for...

Since their breakthrough in 2011, MXenes, transition metal carbides, and/or nitrides have been studied extensively. This large family of two-dimensional materials has shown enormous potential as electrode materials for different applications including catalysis, energy storage, and conversion. MXenes are suitable for the aforementioned applications...

Electrical double-layer capacitors (EDLCs) are of increasing importance in energy storage from renewable sources. The properties of the electrode and electrolyte materials influence the energy and power densities of EDLCs. We examined the specific capacitance and ion dynamics of a protic ionic liquid confined in pre-intercalated Ti3C2Tx MXene. Our...

Developing efficient antibacterial nanomaterials has potential across diverse fields, but it requires a deeper understanding of material‐bacteria interactions. In this study, a novel 2D core‐shell MoAlB@MBene structure is synthesized using a mild wet‐chemical etching approach. The growth of E. coli, S. aureus, and B. subtilis bacteria in the presen...

TiO2/MXene heterostructure has garnered significant interest as a photocatalyst due to its large surface area and efficient charge carrier separation at the interface. However, current synthesis methods produce TiO2 without clear crystal faceting and often require complicated postprocessing step, limiting its practical applications. We demonstrate...

Currently, over 60% of the world's population lives in cities. Urban living has many advantages but there are also challenges regarding the need for smart urbanization. The next generation of tunable 2D nanomaterials, called MXenes, is the critical enabling technology that can bring the current urban thinking to the next level, called a smart city....

Intercalation is a powerful approach to customize the properties of layered materials such as titanium carbide (Ti3C2Tx) MXenes. Photonic curing, a novel technique employing intense pulsed light from a xenon flashlamp (≈280–1100 nm wavelength range), offers significant advantages over conventional annealing methods. The pulsed nature of photonic cu...

MXene is investigated as an electrode material for different energy storage systems due to layered structures and metal‐like electrical conductivity. Experimental results show MXenes possess excellent cycling performance as anode materials, especially at large current densities. However, the reversible capacity is relatively low, which is a signifi...

The development of electrodes with high performance and long‐term stability is crucial for commercial application of vanadium redox flow batteries (VRFBs). This study compared the performance of VRFB with thermal‐treated and MXene‐modified carbon paper. To prepare the MXene, a modified‐etching process with ammonium−bifluoride (NH4HF2) led to a mild...

MBenes are post-MXene materials that contain boron in their structure instead of carbon and nitrogen. This unique composition offers an opportunity to explore the role of boron in the performance of two-dimensional (2D) materials. However, wet-chemical etching and delamination of starting MoAlB phase are challenging due to the persistent bonding of...

Efficient lubrication under harsh conditions is essential for aerospace, automotive, and electrical systems. Novel two-dimensional (2D) materials can serve for this purpose by providing materials with low friction and excellent wear-resistance under these conditions. Therefore, we studied the solid lubrication performance of a novel boridene phase...

Solution-based processing offers advantages for producing thin films due to scalability, low cost, simplicity, and benignity to the environment. Here, we develop conductive and photoactivated self-cleaning reduced graphene oxide (rGO)/Ti3CNTx MXene thin films via spin coating under ambient conditions. The addition of a thin rGO layer on top of Ti3C...

Two-dimensional (2D) transition metal carbides/nitrides (MXenes) are potential antibacterial agents. However, their activity against microorganisms is not fully understood. It could relate to MXenes' surface which further influences their biocidal action. Herein, we report no continuous biocidal activity for delaminated 2D niobium-based MXenes (Nbn...

Lithium‐ion and sodium‐ion batteries (LIBs and SIBs) are crucial in our shift toward sustainable technologies. In this work, the potential of layered boride materials (MoAlB and Mo2AlB2) as novel, high‐performance electrode materials for LIBs and SIBs, is explored. It is discovered that Mo2AlB2 shows a higher specific capacity than MoAlB when used...

The family of two-dimensional (2D) transition-metal carbides, carbonitrides, and nitrides, known as MXenes, has grown from a single composition in 2011 to a ~50-composition family. With a large number of possible transition metals and their combinations, four possible 2D thickness ranges for a single 2D flake, tunable surface chemistry and the capa...

Herein, we report the synthesis of TiO2–SnO2–C/carbide hybrid electrode materials for Li‐ion batteries (LIBs) via two different methods of controlled oxidation of layered Ti2SnC. The material was partially oxidized in an open‐air furnace (OAF) or using a rapid thermal annealing (RTA) approach to obtain the desired TiO2–SnO2–C/carbide hybrid materia...

Rapidly developing nanotechnologies and their integration in daily applications may threaten the natural environment. While green methods of decomposing organic pollutants have reached maturity, remediation of inorganic crystalline contaminants is major problem due to their low biotransformation susceptibility and the lack of understanding of mater...

Transition Metal Carbo‐Chalcogenides In article number 2200574, Michael Naguib and co‐workers report on the synthesis of 2D transition metal carbo‐chalcogenides (TMCCs) by exfoliating their bulk layered counterparts (e.g., Nb2S2C and Ta2S2C) through electrochemical Li‐ion intercalation followed by agitation in water. 2D TMCCs combine the surface of...

Mixed-metal oxides (MMOx), oxides with more than one (transition) metal, provide versatile structural and electrochemical properties well exploited in energy conversion and electrochemical energy storage. The preparation of MMOx from single-source precursors benefits from homogeneous composition and uniform metal distribution. Herein, we describe l...

Here we report a new family of two‐dimensional transition metal carbo‐chalcogenides (TMCCs), which can be considered a combination of two well‐known families, TM carbides (MXenes) and TM dichalcogenides (TMDCs), at the atomic level. Single sheets are successfully obtained from multilayered Nb2S2C and Ta2S2C using electrochemical lithiation followed...

MXene‐transition metal dichalcogenide (TMD) heterostructures are synthesized through a one‐step heat treatment of Nb2C and Nb4C3. These MXenes are used without delamination or any pre‐treatment. Heat treatments accomplish the sacrificial transformation of these MXenes into TMD (NbS2) at 700 and 900 °C under H2S. This work investigates, for the firs...

Electrochemical ion separation is a promising technology to recover valuable ionic species from water. Pseudocapacitive materials, especially 2D materials, are up‐and‐coming electrodes for electrochemical ion separation. For implementation, it is essential to understand the interplay of the intrinsic preference of a specific ion (by charge/size), k...

Two-dimensional (2D) materials offer advantages that their 3D counterparts do not. The conventional method for the bulk synthesis of 2D materials has predominantly been through etching layered solids. Herein, we convert – through a bottom-up approach – 10 binary and ternary titanium carbides, nitrides, borides, phosphides, and silicides into 2D fla...

Two-dimensional (2D) layered transition metal carbides/nitrides, called MXenes, are attractive alternative electrode materials for electrochemical energy storage. Owing to their metallic electrical conductivity and low ion diffusion barrier, MXenes are promising anode materials for sodium-ion batteries (SIBs). Herein, we report on a new 2D carbonit...

In this paper, we report, for the first time, on the electrochemical catalytic activity of 2D titanium carbonitride MXene for hydrogen evolution reaction (HER). According to our study, 2D titanium carbonitride exhibited much higher electrocatalytic activity than its carbide analogues, achieving an onset overpotential of 53 mV and Tafel slope of 86...

In this article, Michael Naguib and co-authors (DOI: 10.1002/inf2.12269) report on the successful synthesis and characterization of a new 2D carbonitride MXene, viz. Ti2C0.5N0.5, which is the only second carbonitride MXene. They explore the performance of this new MXene as electrode materials for sodium-ion batteries (SIBs) and it outperformed its...

MXenes In article number 2103393, Michael Naguib, Michel W. Barsoum, and Yury Gogotsi present a brief historical overview of the first 10 years of MXene research and a perspective on their synthesis and future development. The cover shows a colored SEM image of a multilayer Ti3C2 MXene particle with an accordion-like morphology, which is produced b...

MXene-based Lightning Strike Protection Coating In article number 2100803, Vipin Kumar and co-workers investigate MXene as an effective filler to improve the electrical and mechanical properties of divinylbenzene (DVB) thermosetting resin. Its performance as a lightning strike protection coating for carbon fiber reinforced polymer (CFRP) is evaluat...

Since their discovery in 2011, the number of 2D transition metal carbides and nitrides (MXenes) has steadily increased. Currently more than 40 MXene compositions exist. The ultimate number is far greater and in time they may develop into the largest family of 2D materials known. MXenes’ unique properties, such as their metal‐like electrical conduct...

Interlayer Spacing In article number 2104007, Michael Naguib and co-workers report the engineering of interlayer spacing of multilayer MXene—by pre-intercalation of pillars—to host large-size cations of room temperature ionic liquids in between the layers, achieving high energy density supercapacitors. An optimum interlayer spacing of 2.2 nm (for p...

Ti3C2 – a member of the MXenes (two-dimensional (2D) transition metal carbides and nitrides) family, is investigated as an effective filler to improve the electrical, mechanical, and thermal properties of divinylbenzene (DVB) thermosetting resin. Consequently, its performance as a lightning strike protection (LSP) coating for carbon fiber reinforce...

MXenes exhibit excellent capacitance at high scan rates in sulfuric acid aqueous electrolytes, but the narrow potential window of aqueous electrolytes limits the energy density. Organic electrolytes and room‐temperature ionic liquids (RTILs) can provide higher potential windows, leading to higher energy density. The large cation size of RTIL hinder...

Herein we report on using Egyptian blue as an anode material for Li-ion batteries. A 1st cycle lithiation capacity of 594 mA h g-1 and reversible capacity of 210 mA h g-1 at 20 mA g-1, and at 500 mA g-1 a reversible capacity of 120 mA h g-1 (stable over 1000 cycles) were achieved with coulombic efficiency more than 99.5%. Using X-ray diffraction, a...

Herein we report an approach to synthesis Ti3AlC2 MAX phase and Ti3C2Tz MXene from low-cost precursors, viz. recycled carbon recovered from waste tire, recycled aluminum scrap, and titanium oxide. By adjusting the ratios of the initial materials, we determined that 3TiO2+6Al+1.9C resulted in the purest sample of Ti3AlC2 when heated at 1,350 °C for...

Thermal safety concerns of lithium ion batteries (LIBs) need to be solved urgently to facilitate their large-scale applications. Introducing safer anode materials can suppress the thermal runaway initiation but is usually compromising the cell performance due to their induced lower energy density. In this work, Ti3C2Tz MXene with tailored surface t...

Layered titanium carbide (Ti3C2T x ) MXene is a promising electrode material for use in next-generation electrochemical capacitors. However, the atomic-level information needed to correlate the distribution of intercalated cations with surface redox reactions, has not been investigated in detail. Herein we report on sodium preintercalated MXene wit...

An “Evaporated-Nitrogen” Minimally Intensive Layer Delamination (EN-MILD) synthesis approach is originally reported to synthesize exceptionally high quality MXene sheets. In EN-MILD method, the concentration of acids and Li-ion are continuously increased during the etching process. By implementing EN-MILD approach, the electrical conductivity incre...

The synthesis of heterostructures of different two-dimensional (2D) materials offers an approach to combine advantages of different materials constituting the heterostructure and ultimately enhance their performance for applications such as electrochemical energy storage, achieving high energy, and high-power densities. Understanding the behavior o...

Two-dimensional (2D) MXenes have demonstrated outstanding antimicrobial properties owing to their unique physiochemical properties and ultrathin lamellar structure. However, the relationship between MXene sheet size and their antimicrobial activity and how the atomic structure can impact the antibacterial mechanism are yet to be revealed. This stud...

Herein we report on the catalytic activity of Ti‐based MXenes (Ti3CNTz and Ti3C2Tz) for biomass transformation. MXenes were found to be active catalysts for the hydrogenation of furfural using either gaseous hydrogen or 2‐propanol as solvent and hydrogen source. Both catalysts showed good activity in the conversion of furfural to furfuryl alcohol,...

MAX phases are etched using an ionic liquid-water mixture to produce titanium carbide MXenes. The process avoids the use of any acid. Hydrolysis of the fluorine-containing ionic liquid leads to...

In this work, we study the electrochemical performance of Nb2CTx and Nb4C3Tx MXenes in aqueous media and their application as a sensing platform for small biomolecules. Both Nb2CTx and Nb4C3Tx are electrochemically stable up to an anodic potential of 0.5 V. It was found that Nb4C3Tx is more electrochemically active than Nb2CTx. Based on this, Nb4C3...

Enhancing the energy stored and power delivered by layered materials relies strongly on improved understanding of the intricate interplay of electrolyte ions, solvents, and electrode interactions as well as the role of confinement. Here we report a highly integrated study with multiscale theory/modelling and experiments to track the intercalation o...

Ti3C2Tx MXene is a two dimensional (2D) material possessing highly active hydrophilic surfaces coupled with high metallic conductivity. Cations intercalation between the Ti3C2Tx nanosheets has a significant role in many applications such as water purification, desalination, and electrochemical energy storage. The pseudocapacitive charging mechanism...

A Nb4C3Tx (MXene)-modified glassy carbon electrode was used for the electrochemical detection of Pb²⁺ ions in aqueous media. The sensing platform was evaluated by anodic stripping analysis after optimizing the influencing factors such as pH, deposition potential, and time. The large interlayer spacing, high c lattice parameter and higher conductivi...

Since the discovery of two-dimensional transition metal carbides, referred to as MXenes, research efforts targeted their applications in energy storage, as lithium-ion batteries and supercapacitors. This interest is attributable to MXenes’ large volumetric capacitance, high rate handling capability and stable cycling performance, which largely rely...

There are several problems that need to be overcome to enable smooth and sustainable clinical translation of the MXene materials, including hard controllable surface chemistry. In this study, we show for the first time that by using surface modification with poly-L-lysine (PLL), it is possible to completely invert the highly negative surface charge...

A comprehensive study on the prototype solid solution phase carbonitride MXene Ti3CN is conducted using nuclear magnetic resonance, electron spin resonance, total and quasi‐elastic neutron scattering, combined with density functional theory‐based electronic structure and molecular dynamic calculations. The combination of experiment and theory lead...

MXene liquid crystals, made of only water and MXene, coagulate to form a multifunctional electrically conductive pure MXene fiber.

Intercalation in Ti3C2T x MXene is essential for a diverse set of applications such as water purification, desalination, electrochemical energy storage, and sensing. The interlayer spacing between the Ti3C2T x nanosheets can be controlled by cation intercalation; however, the impact of intercalation on the Ti3C2T x MXene chemical and electronic str...

Here we demonstrate the theory-guided plasma synthesis of high purity nanocrystalline Li3.5Si0.5P0.5O4 and fully amorphous Li2.7Si0.7P0.3O3.17N0.22. The synthesis involves the injection of single or mixed phase precursors directly into a plasma torch. As the material exits the plasma torch, it is quenched into spherical nanocrystalline or amorphous...

The redox reaction of intercalated protons is key to pseudocapacitance of MXenes (2D carbides and nitrides) in H2SO4. However, atomistic understanding of proton redox and transfer in water confined between MXene layers is still lacking. Here we use first-principles molecular dynamics (FPMD) simulations to reveal the proton-transfer mechanism in MXe...

MXenes have hydrophilic interlayer spaces that can accommodate a large variety of intercalants. These are typically molecules such as H2O or dimethylsulfoxide (DMSO) or ions such as metal or ammonium cations. This chapter summarizes the body of literature that has explored exactly what compositions of intercalants have been studied, the nature and...

Since the discovery of 2D transition metal carbides, nitrides, or carbonitride MXenes, methods have been developed to optimize and control synthesis. Two-dimensional MXenes are generally synthesized through the selective etching of the parent MAX phase using etchants based on acidic fluoride solution. However, the specific etchant and etching param...

Herein we report on the characterization of a Li-S hybrid cell containing a garnet solid electrolyte (Li7La3Zr2O12, LLZO) and conventional liquid electrolyte. While the liquid electrolyte provided ionically conductive pathways throughout the porous cathode, the LLZO acted as a physical barrier to protect the Li metal anode and prevent polysulfide s...

Use the link below to get free access to download paper until October 10th 2019. https://authors.elsevier.com/c/1Zbi7925JE9eWf

Titanium dioxide, TiO2, represents a promising candidate for hydrogen production via photocatalysis. However, its large bandgap and fast charge recombination limits its efficiency. To overcome this limitation, we explored in this work two-dimensional titanium carbide MXene, Ti3C2Tx (Tx = O, OH, F), as feasible co-catalysts for hydrogen production w...

Lithium phosphorus oxynitride (Lipon) is the most prominent example of glassy oxynitride electrolytes, which have demonstrated high ionic conductivities, stability over a wide voltage window, and resistance to Li dendrite formation. ¹ Perhaps the greatest drawback of glassy oxynitride electrolytes is that expensive, high-vacuum deposition technique...

As a new class of 2D materials, MXene has triggered attention because of its exceptional electrical and mechanical properties. MXene’s excellent electrical conductivity and hydrophilicity, make it an ideal option for solution-based polymer nanocomposite fabrication. For the first-time polymer nanocomposites of polyvinyl alcohol (PVA)/Ti3C2Tx (MXene...

Photocatalytic hydrogen evolution from water has received enormous attention due to its ability to address a number of global environmental and energy-related issues. Here, we synthesize 2D/2D Ti3C2/g-C3N4 composites by electrostatic self-assembly technique and demonstrate their use as photocatalysts for hydrogen evolution under visible light irrad...

MXenes (two-dimensional transition metal carbides and nitrides) are promising materials for capacitive energy storage due to the large chemical space of existing and potential compositions, but only a few of them have been experimentally explored. In this work, we computationally screen a series of MXene electrodes (Mn+1XnTx: M=Sc, Ti, V, Zr, Nb, M...

Multi-modal gravimetric, direct-current electrical, and electrical impedance sensor modalities of high surface area of 2D materials MXenes (Ti3C2) was exposed to pulses of H2O vapor spanning 3 orders of magnitude (20 mTorr - 20 Torr). The Ti3C2 film exhibited reproducible, reversible response in 0.1%-95% RH humidity range with a detection limit of...

MXenes are a new class of two-dimensional materials with properties that make them important for applications that include batteries, capacitive energy storage and electrocatalysis. These materials can be exfoliated to create high surface areas with interlayer accessibility. Intercalation is known to be possible and it is critical for many applicat...

The oxidation of two-dimensional Ti3C2 MXene structures has been recognized as a promising method for the formation of hybrid structures of carbon supported nanotitania. Here, we studied the oxidation of Ti3C2 MXene structures using reactive force field (ReaxFF) based molecular dynamics simulations. To investigate the effect of oxidizing agent, we...

The composition, morphology and thickness of solid electrolyte interphase (SEI) on silicon anodes are dictated by multiple factors, ranging from the chemistry of silicon surfaces, electrolyte solution structure and chemical passivation on Si surface. In addition, the SEI constantly evolves, as it is electrochemically lithiated (delithiated) due to...

MXenes have attracted great attention as next-generation capacitive energy-storage materials, but the mechanisms underlying their pseudocapacitive behavior are not well understood. Here we provide a theoretical description of the surface redox process of Ti3C2Tx (T=O, OH), a prototypical MXene, in 1M H2SO4 electrolyte, based on joint density functi...

Although significant progress has been made in improving cycling performance of silicon-based electrode, few studies have been performed on the architecture effect on polymer binder performance for lithium-ion batteries. A systematic study on the relationship between polymer architectures and binder performance is especially useful in designing syn...

Hydrogen production through facile photocatalytic water splitting is regarded as a promising strategy for solving global energy problems. Transition metal carbides (MXenes) have recently drawn attention as potential co-catalyst candidates for photocatalysts. Here, we report niobium pentoxide/carbon/niobium carbide (MXene) hybrid materials (Nb2O5/C/...

We report on a unique safety mechanism introduced to the Li-ion battery design to mitigate the effects of a mechanical impact event by limiting the current moving through resulting internal shorts, thereby preventing thermal runaway. “Slitted” electrodes and current collectors would electrically isolate the impacted parts of the electrodes before p...

Two-dimensional (2D) carbides and nitrides of early transition metals (MXenes) combine high conductivity with hydrophilic surfaces, which make them promising for energy storage, electrocatalysis, and water desalination. The effects of intercalated metal ions on the vibrational states of water confined in Ti3C2Tx MXenes have been explored using inel...