Controlled Synthesis, Processing, and Applications of Structural and Functional Nanomaterials: 2D Materials Synthesis & Properties
Sponsored by: ACerS Basic Science Division, ACerS Electronics Division, ACerS Engineering Ceramics Division
Program Organizers: Haitao Zhang, University of North Carolina at Charlotte; Gurpreet Singh, Kansas State University; Kathy Lu, University of Alabama Birmingham; Edward Gorzkowski, Naval Research Laboratory; Jian Shi, Rensselear Polytechnich University; Michael Naguib, Tulane University; Sanjay Mathur, University of Cologne
Monday 8:00 AM
October 10, 2022
Room: 320
Location: David L. Lawrence Convention Center
Session Chair: Michael Naguib, Tulane University ; Haitao Zhang, University of North Carolina at Charlotte
8:00 AM Keynote
Near-field Imaging of 2D-heterostructures: Portraying Optical Nonuniformity at the Nanoscale: Slava V Rotkin1; 1The Pennsylvania State University
Atomically thin two-dimensional materials (2DM) have an ultimate surface-to-volume ratio. While it helps biosensing and other applications, surface non-uniformities may drastically increase variability of materials properties. Using an example of a vertical 2DM heterostructure comprised of monolayer graphene and single layer flakes of MoS2, we introduce a novel multidimensional optical imaging technique, capable to detect lattice mismatch and work function difference in the heterostructure. Those result in strain and charge transfer and vary optical response at the nanometer scale, hard to detect and study by other characterization tools. Furthermore, the near-field microscopy allows mapping of distribution for doping and strain at sub-diffractional resolution, that correlate with the non-uniform broadening of optical response of the heterostructure. In summary, multidimensional optical nanoscale imaging allows one to understand the physics of electronic response of 2D materials and their heterostructures. Acknowledgement: partial support from NSF CHE-2032582, CHE-2032601, DMR-1539916 and DMR-2011839.
8:30 AM Invited
Visualizing Complex Many-body Phenomena in Atomically Thin Quantum Materials: Jyoti Katoch1; 1Carnegie Mellon University
Two-dimensional (2D) materials offer the freedom to create novel condensed matter systems, with unique properties, by mechanically assembling different (or same) 2D materials layer-by-layer to form atomically sharp vertical or lateral heterostructures. The van der Waals (vdW) heterostructures with small lattice mismatch and a relatively small twist angle between the constituent layers, have shown to exhibit coexisting complex phases of matter including Mott insulating state, superconductivity, bound quasiparticles, and topological states. The advent of the state-of-the-art angle-resolved photoemission spectroscopy with high spatial resolution (micro- and nano-ARPES) and the ability to perform these measurements on fully functional devices, has made it possible to directly probe many exotic physical phenomena in 2D based material systems. In this talk, I will discuss the utilization of the nanoARPES to investigate the highly tunable many-body effects in 2D based heterostructures and their devices.
9:00 AM
Synthesis of Solid-Solution MXenes with Tunable Electronic, Optical, and Electrochemical Properties: Christopher Shuck1; Meikang Han1; Kathleen Maleski1; Yizhou Yang1; James Glazar2; Alexandre Foucher2; Kanit Hantanasirisakul1; Asia Sarycheva1; Nathan Frey2; Steven May1; Vivek Shenoy2; Eric Stach2; Yury Gogotsi1; 1Drexel University; 2University of Pennsylvania
MXenes are the largest class of 2D materials discovered so far. With a general formula of Mn+1XnTx, M is an early transition metal, X is C and/or N, Tx represents the surface groups, and n = 1–4, over 30 stoichiometric phases have already been discovered. One understudied class of MXenes are solid-solution, where multiple elements are randomly distributed within the M layers. Herein, three interrelated solid solution systems, (Ti2-yVy)CTx, (Ti2-yNby)CTx, (Nb2-yVy)CTx are used as models to study the optical, electronic, and electrochemical properties. Optically, the MXene systems are tailorable in a nonlinear fashion, with absorption peaks from ultraviolet to near-infrared wavelength. The electrical conductivity of solid solution MXenes can be controllably varied over 6 orders of magnitude from 10 to 300 K. They exhibit tunable properties that are directly related to their chemistry. By understanding this relationship, it then becomes possible to rationally design MXenes designed for specific applications.
9:20 AM
Safer Etching of Ti3AlC2 MAX Phases to Directly Yield Ti3C2Tz MXene Nanosheets Using Quarternary Ammonium Fluorides: Vrushali Kotasthane1; Zeyi Tan1; Junyeong Yun1; Jodie Lutkenhaus1; Micah Green1; Miladin Radovic1; 1Texas A&M University
MXene are commonly synthesized by selective etching of A element from a parent MAX in HF or mixtures of alkali fluorides and HCl, followed by their intercalation and exfoliation. However, the health hazards associated with using highly toxic chemicals in their synthesis still remain on of the major concerns for scaling up MXene production. To address this challenge, a safer process is used in this study consisting of a simultaneous etching and exfoliation using mixture of tetramethylammonium fluoride (TMAF) and HCl at room temperature. The large size of the quaternary ammonium ion was found to promote intercalation and exfoliation during etching, and thus MXene nanosheets were obtained with yields exceeding 30% directly during etching without need for post-etching intercalation and exfoliation as in the case of conventional synthesis. The functional group distribution of the Ti3C2Tz was found to vary with the etching duration and the morality of TMAF and HCl.
9:40 AM
Transition Metal Carbo-Chalcogenide “TMCC” a New Family of Two-dimensional Materials: Ahmad Majed1; Manish Kothakonda1; Fei Wang1; Eric Tseng2; Kaitlyn Prenger1; Xiaodon Zhang1; Per Persson2; Jiang Wei1; Jianwei Sun1; Michael Naguib1; 1Tulane University; 2Linköping University
Developing new nanomaterials opens the door for signifcnat technological development. In this presentation we will report on introducing a new family of two-dimensional (2D) transition metal carbo-chalcogenides (TMCCs). TMCCs can be considered as a merge between two well-known families: MXenes and transition metal dichalcogenides (TMDCs), at the atomic level. 2D Nb2S2C and Ta2S2C are the first members of TMCCs and they were delaminated from their parent multilayered structures via electrochemical lithiation followed by liquid exfoliation in water. Electronic and magnetic properties of Nb2S2C multilayers were studied, a superconductivity transition is observed at 7.55 K. When tested as electrodes for Li-ion batteries, the delaminated Nb2S2C surpasses both multilayered Nb2S2C and delaminated NbS2 in terms of capacity and stability. In addition, Ab initio calculations predicted elastic constant of TMCC to be 50% higher than that of TMDCs.
10:00 AM Break
10:20 AM Invited
Exciton Physics at the Atomic Scale: Dan Gunlycke1; 1U.S. Naval Research Laboratory
Descriptions of excitons in pristine semiconducting crystals usually rely on the hydrogen model adopted for excitons. Owing to the weak screening in monolayer transition-metal dichalcogenides, however, the electron and hole separation in the strongest bound excitons is on the atomic scale, necessitating atomistic treatment. In this presentation, we present a minimalistic exciton model that accounts for the lattice and the spin-orbit and exchange interactions, thus making this model appropriate across the spectrum from Wannier to Frenkel excitons. Using this model, we show that the exciton lifetimes could be extended by transitioning the excitons into excitonic dark states. Longer exciton lifetimes could make these materials candidates for applications in energy management and quantum information processing.This work has been supported by the Office of Naval Research (ONR), directly and through the Naval Research Laboratory (NRL).
10:50 AM Invited
Synthesis of Nanolamellar Ultra-high Temperature Carbides by High-temperature Phase Transformation of 2D MXenes: Babak Anasori1; 1Purdue School of Eng. & Tech., IUPUI
Two-dimensional transition metal carbides, nitrides, and carbonitrides, known as MXenes, have a wide array of impressive material properties due to their inherent transition metal carbide and nitride core with abundant surface functionalities. Few studies take advantage of the inherent stability of MXenes’ interior transition metal carbide core. While MXenes can be oxidized in air, they can be transformed to ultra-high temperature carbides with controlled morphology and crystal orientation under a controlled environment. In this talk, we present the high-temperature behavior of Ti3C2Tx from room temperature to 2000 °C in an inert atmosphere. We discuss how the starting morphology of MXene controls the resulting ultra-high temperature carbide ceramics. For example, nanolamellar Ti2C and highly textured TiCy carbides are formed by annealing Ti3C2Tx MXene single-flake films. These findings identify a unique capability of MXenes for future studies to form highly stable MXene-derived carbides and nitrides with controlled morphology for extreme environment applications.
11:20 AM Cancelled
Superior Mechanical and Functional Properties of Thin Film Materials with Terrace-defect Interface Induced Nanostructures: Jian Song1; Yue Liu1; Xinghang Zhang2; 1Shanghai Jiao Tong University; 2Purdue University
Using interfacial strain to control the physical properties of thin film is an effective strategy in elastic strain engineering. However, interfacial strain quickly decays with increase of film thickness, thereby hindering their applications. Here, we demonstrated a new strategy that can tailor physical properties of thin film by introducing planar defects through the periodic local elastic strain of heterogeneous terrace-defect interfaces. Using Cu (100) seed layer, we synthesized micron-thick fcc Co films with three-dimensional nanoscale stacking faults (3D-nSFs) that could achieve high strengths without sacrificing soft magnetic properties. The 3D-nSFs, induced by Co/Cu interface, could not only stabilize the metastable fcc-Co to yield lower coercivity but also impede dislocation motion to strengthen Co films. Moreover, we tailored the density of 3D-nSFs and confirmed a large variation in coercivity (by 100%) and indentation-hardness (by 25%). This work provides a new strategy for integrated performance optimization by interface design and strain engineering.
11:40 AM
Scalable Synthesis of Titanium Carbo-oxides Nanofilaments and 2D Flakes, Their Properties, and Potential Applications: Hussein Badr1; Michel Barsoum1; 1Drexel University
Two-dimensional (2D) materials thrive on the rich variety of features that are distinctive from their bulk counterparts. Conventionally, bulk synthesis of 2D materials has predominantly been through etching of layered solids. Herein and for the first time, we convert – at near ambient conditions – a dozen of cheap, versatile, water insoluble Ti-containing powders into anatase-based nanofilaments that self-assemble in 2D sheets. The resulting structures were characterized using a battery of characterization techniques. Electrodes of the flakes performed well in Li-ion and Li-S battery. The flakes also were found to be fatal for cancer cells. Synthesizing 2D materials in bulk at near ambient conditions is paradigm shifting and will open new and exciting avenues of research/applications.
12:00 PM
Synthesis of Functional Semiconducting Metal-sulfide Materials by Molecular Building Blocks: Veronika Brune1; Sanjay Mathur1; 1University of Cologne
The unique physical properties of low-dimensional metal sulfide materials have attracted great attention in sustainable several energy storage and conversion applications. The ultrahigh surface area of nanostructured semiconductors in combination with their extraordinary physiochemical, electronic and optical properties offer the application as catalysts. The huge number of active sides of 2D van der Waals materials like transition metal disulfides (TMDC) and monosulfides (MS), as well as their suitable and tunable band gap offer their application in energy conversion devices. The lacking control of large-scale material synthesis corresponding to specific requirements in commercial material formation processes is still challenging, which motivated us to develop a unique synthetic approach to low-dimensional layered materials MS2 (MIV= Mo, W, Ti, Nb, Ta, Sn) and MS (MII=Sn, Ge). A uniform synthesis route of molecular building blocks for controlled formation of (air)stable precursor classes [M{S(C2H4)2NMe}x] (x = 1, 2) was developed.