A5020649130- Graphene research and applications
- Carbon Nanotubes in Composites
- 2D Materials and Applications
- Molecular Junctions and Nanostructures
- Advancements in Battery Materials
- Advanced Memory and Neural Computing
- Nanowire Synthesis and Applications
- Semiconductor materials and devices
- Mechanical and Optical Resonators
- Force Microscopy Techniques and Applications
- Organic Electronics and Photovoltaics
- MXene and MAX Phase Materials
- Conducting polymers and applications
- Advanced Sensor and Energy Harvesting Materials
- Perovskite Materials and Applications
- Graphene and Nanomaterials Applications
- Quantum and electron transport phenomena
- Surface and Thin Film Phenomena
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Ferroelectric and Negative Capacitance Devices
- Nanotechnology research and applications
- Supercapacitor Materials and Fabrication
- Advanced Battery Materials and Technologies
- Boron and Carbon Nanomaterials Research
Northwestern University
2016-2025
Materials Science & Engineering
2006-2025
Materials Research Center
2025
Fermi National Accelerator Laboratory
2024
Midwestern University
2022-2024
University of Illinois Urbana-Champaign
1998-2021
Center for Light Energy Activated Redox Processes
2019-2021
Robert H. Lurie Comprehensive Cancer Center of Northwestern University
2021
Sejong University
2020
Clemson University
2020
At the atomic-cluster scale, pure boron is markedly similar to carbon, forming simple planar molecules and cage-like fullerenes. Theoretical studies predict that two-dimensional (2D) sheets will adopt an atomic configuration of clusters. We synthesized atomically thin, crystalline 2D (i.e., borophene) on silver surfaces under ultrahigh-vacuum conditions. Atomic-scale characterization, supported by theoretical calculations, revealed structures reminiscent fused clusters with multiple scales...
With advances in exfoliation and synthetic techniques, atomically thin films of semiconducting transition metal dichalcogenides have recently been isolated characterized. Their two-dimensional structure, coupled with a direct band gap the visible portion electromagnetic spectrum, suggests suitability for digital electronics optoelectronics. Toward that end, several classes high-performance devices reported along significant progress understanding their physical properties. Here, we present...
Unencapsulated, exfoliated black phosphorus (BP) flakes are found to chemically degrade upon exposure ambient conditions. Atomic force microscopy, electrostatic transmission electron X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy employed characterize the structure chemistry of degradation process, suggesting that O2 saturated H2O irreversibly reacts with BP form oxidized species. This interpretation is further supported by observation occurs more rapidly on...
Graphene flakes with controlled thicknesses are isolated in solution using density gradient ultracentrifugation. These stable graphene dispersions produced the bile salt sodium cholate, which promotes graphite exfoliation and results graphene−surfactant complexes having buoyant densities that vary thickness. The sorted characterized atomic force microscopy Raman spectroscopy. differentiation offer superior performance transparent conductors than those conventional sedimentation-based...
Solution dispersions of two-dimensional (2D) black phosphorus (BP), often referred to as phosphorene, are achieved by solvent exfoliation. These pristine, electronic-grade BP produced with anhydrous, organic solvents in a sealed tip ultrasonication system, which circumvents degradation that would otherwise occur via solvated oxygen or water. Among conventional solvents, n-methyl-pyrrolidone (NMP) is found provide stable, highly concentrated (~0.4 mg/mL) dispersions. Atomic force microscopy,...
Abstract Two-dimensional (2D) layered materials have attracted significant attention for device applications because of their unique structures and outstanding properties. Here, a field-effect transistor (FET) sensor is fabricated based on 2D phosphorene nanosheets (PNSs). The PNS exhibits an ultrahigh sensitivity to NO 2 in dry air the dependent its thickness. A maximum response observed 4.8-nm-thick PNS, with up 190% at 20 parts per billion (p.p.b.) room temperature. First-principles...
The exceptional properties of graphene enable applications in electronics, optoelectronics, energy storage, and structural composites. Here we demonstrate a 3D printable (3DG) composite consisting majority minority polylactide-co-glycolide, biocompatible elastomer, 3D-printed from liquid ink. This ink can be utilized under ambient conditions via extrusion-based printing to create structures with features as small 100 μm composed few two layers (<300 thick object) or many hundreds (>10 cm...
The ability to print high conductivity, conformal, and flexible electrodes is an important technological challenge in printed electronics, especially for large-area formats with low cost considerations. In this Letter, we demonstrate inkjet-printed, conductivity graphene patterns that are suitable electronics. ink prepared by solution-phase exfoliation of using environmentally benign solvent, ethanol, a stabilizing polymer, ethyl cellulose. inkjet-printed features attain resistivity 4 mΩ·cm...
We investigate the limits of high energy transport in multiwalled carbon nanotubes (MWNTs). In contrast to metal wires, MWNTs do not fail continuous, accelerating manner typical electromigration. Instead, they via a series sharp, equally sized current steps. assign these steps sequential destruction individual nanotube shells, consistent with MWNT's concentric-shell geometry. Furthermore, initiation this failure is very sensitive air exposure. initiated by oxidation at particular power,...
While graphene oxide (GO) has been found to be the most toxic graphene-based nanomaterial, its environmental fate is still unexplored. In this study, aggregation kinetics and stability of GO were investigated using time-resolved dynamic light scattering over a wide range aquatic chemistries (pH, salt types (NaCl, MgCl2, CaCl2), ionic strength) relevant natural engineered systems. Although pH did not have notable influence on from 4 10, type strength had significant effects due electrical...
With its unique electronic and optical properties, graphene is proposed to functionalize tailor titania photocatalysts for improved reactivity. The two major solution-based pathways producing graphene, oxidation-reduction solvent exfoliation, result in nanoplatelets with different defect densities. Herein, we show that nanocomposites based on the less defective solvent-exfoliated exhibit a significantly larger enhancement CO(2) photoreduction, especially under visible light. This...
To facilitate the proposed use of graphene and its derivative oxide (GO) in widespread applications, we explored strategies that improve biocompatibility nanomaterials lung. In particular, solutions aggregated graphene, Pluronic dispersed GO were administered directly into lungs mice. The introduction resulted severe persistent lung injury. Furthermore, cells increased rate mitochondrial respiration generation reactive oxygen species, activating inflammatory apoptotic pathways. contrast,...
The bulk enrichment and separation of single-walled carbon nanotubes (SWNTs) by diameter has been achieved through ultracentrifugation DNA-wrapped SWNTs in aqueous density gradients. is identified the visual formation colored bands range 1.11−1.17 g cm-3. optical absorbance spectra separated indicate that decreasing are increasingly more buoyant. This nondestructive scalable strategy expected to impact fields molecular electronics, optoelectronics, sensing where a monodisperse band gap essential.
Thin film transistors (TFTs) are now poised to revolutionize the display, sensor, and flexible electronics markets. However, there is a limited choice of channel materials compatible with low-temperature processing. This has inhibited fabrication high electrical performance TFTs. Single-walled carbon nanotubes (CNTs) have very mobilities can be solution-processed, making thin CNT-based TFTs natural direction for exploration. The two main challenges facing CNT-TFTs difficulty placing aligning...