Adrian Hightower, PhD, PE, ENV-SP’s Post

#Graphene edges can be used as #nanoelectrodes for #electrochemistry, new #research shows. Researchers from five countries have joined hands to produce protruding graphene edges in a #nanostructure, and to perform cyclic #voltammetry with #reactions on the edge. This method allowed for detection of #redox species down to #micromolar concentrations with sub-second time resolution. The research opens a path towards electrochemistry on a #chip with a number of #electrodes in parallel, as well as the use of low volumes of sample solution, and new effects such as studying electron transfer without an #electrolyte. https://lnkd.in/dqChdXTn

Dynamic STEM-EELS for single-atom and defect measurement during electron beam transformations Science Advances https://lnkd.in/g3Abc5Jn

【Technology/Materials】 Direct Observation of the Breaking of Carbon Nanotube Fibers Caused by Molecular Slippage Using a transmission electron microscope, researchers at the University of Tsukuba have directly observed the breaking of carbon nanotube fibers is induced by molecular slippage, involving repeated transitions between static and kinetic friction. Furthermore, they have discovered that this slippage can be considerably suppressed by doping nitrogen into individual carbon nanotube molecules, followed by bundling them into fibers. Specifically, when these nitrogen-doped nanotubes are irradiated with an electron beam, the resulting fibers exhibit enhanced strength. Read more details here; https://lnkd.in/gYE992GC Original Paper; https://lnkd.in/gvQknfXB

Light, Switch, Action! The Influence of Geometrical Photoisomerization in an Adaptive Self-Assembled System👌⚗️🧫🧪🌡️🧬 The ubiquitous ability of natural dynamic nanostructures to adapt to environmental changes is a highly desirable property for chemical systems, particularly in the development of complex matter, molecular machines, and life-like materials. Designing such systems is challenging due to the generation of complex mixtures with responses that are difficult to predict, characterize, and diversify. Here, we navigate between self-assembled architectures using light by operating an intrinsic photoswitchable building block that governs the state of the system. When complementary units are present, the photoswitch determines the predominant architecture, reversibly adapting between the cage and macrocycles, including (otherwise inaccessible) higher-energy assemblies. Our study showcases this concept with seven different transformations, offering an unprecedented degree of control, diversification, and adaptation by self-selecting complementary units. These findings could enable applications of on-demand dissipative macrocycles based on dynamic bonds. We also envision different transient nanostructures, e.g., reticular and polymeric materials, being explored by fine-tuning the nature of the complementary unit. 🛑 I strongly encourage you to view the clip provided below.😍😉👌⚗️🧪🌡️🧬 Reference: https://lnkd.in/dZKdckXb #organicchemistry #nanotechnology #nanomaterials #nanoparticles #fragrances #aromatic #synthesis #DielsAlderreaction #nanomedicine #polymers #nanochemistry #materials #Supramolecularchemistry #greenchemistry #nanoscience #phdposition #greenchemistry #inorganicchemistry #chemistry #newmolecules #nanocomposite #neurological #nanosensor #biochemistry #nanochip #macromolecules #nanomotors #catenane #rotaxane #knot #interlockedmolecules #metalfree #Machinemolecules #Photoisomerization

Nanoporous membranes with atomic-scale holes smaller than one-billionth of a meter have powerful potential for decontaminating polluted water, pulling valuable metal ions from the water, or for osmotic power generators. Under University of Chicago PME Asst. Prof. Chong Liu, the team created a new method of pore generation that builds materials with intentional weak spots, then applies a remote electric field to generate multiple nanoscale pores all at once. Liu said the new Nature Portfolio Communications paper is an intellectual offshoot of an interdisciplinary collaboration with the battery-focused laboratory of PME Prof. Shirley Meng and PME Asst. Prof. Shuolong Yang’s quantum group. Working across academic silos, the three labs previously collaborated to break through a longstanding hurdle in growing quantum qubits on crystals. 🔗https://lnkd.in/gUXk6fPN #UChicagoPME #Research #Materials #Science #Batteries #Water #Nanoscale #Quantum

Dynamic evolution of catalytic nanoparticles during catalysis under reaction conditions has a significant impact on the catalytic activity of a particular catalyst. That is the reason that in most cases, catalytic activity of a catalyst deteriorates with the number of catalytic cycles. As the catalytic activity is a strong function of size, shape, crystallinity and surface facets, the dynamic evolution may increase or decrease the catalytic activity of the catalyst depending on transient structural stages it goes through. Researchers from Zhejiang University, Chinese Academy of Sciences and University of Chinese Academy of Sciences have studied dynamic structural evolution of Pd nanoparticles exposed to hydrogen and oxygen under atmospheric pressure using in-situ transmission electron microscopy (in-situ TEM). When exposed to H₂, Pd nanoparticles appeared to be structurally stable at 200°C. But, at 300°C, the particles underwent sintering to form larger truncated cubic structures. The structural evolution is attributed to the H₂ adsorption as H₂ absorption is less likely due to the instability of Pd hydrides at the temperatures used. On the contrary, exposure to oxygen resulted in truncations on annealing even at 200°C without any evidence of the oxide formation. In-situ TEM investigations were performed on a Thermo Fisher Scientific Tecnai F20 operated at 200 kV with a DENSsolutions Climate gas cell holder. The phase-contrast movie here demonstrates the dynamic structural evolution of the Pd nanocube along [001] ZA orientation exposed to O₂ at 200°C. As the microscope is uncorrected, and in high-resolution mode, larger objective aperture is desired to use, we can see defocus and the third-order spherical aberration (Cₛ) dependent contrast delocalization from the displaced image information carried by the interference between scattered electrons and the unscattered electrons and Miller fringes which is given by, ΔR = λu(∆f + Cₛλ²u²), Where, ∆R = contrast delocalization, λ = electron wavelength, u = spatial frequency, ∆f = defocus, Cₛ = third-order spherical aberration coefficient. Read the interesting study published in the journal Chemical Communications. https://lnkd.in/dqrUPe2k #dynamicevolution #structuralevolution #truncation #facetting #insituTEM #gasphaseTEM #phasecontrast #contrastdelocalization #sphericalaberration #electronmicroscopy

I am thrilled to announce that our latest article is live! In this work, we show that graphene can appear, in STEM images, to be perfectly (atomically) clean but still harbor rapidly diffusing 'invisible' hydrocarbons. With a high enough concentration these 'invisible' hydrocarbons are directly detectable in the image intensity. Understanding their dynamic behavior, how to control them, and how they interact with the electron beam will be critical for pushing electron beam fabrication technology to the limit of atomic precision. In addition, claims of having produced 'clean graphene' should be taken with a healthy dose of skepticism. Even acquiring an atomically resolved STEM image of the graphene, where you can see nothing but atomic lattice, does not conclusively demonstrate that it is clean. The work here, also dovetails nicely with our previous work (https://lnkd.in/gTFv_VnX) where we showed that e-beam deposited corrals were able to block the ingress of hydrocarbons at high temperatures. The general picture that is beginning to emerge is that the behavior of hydrocarbons on surfaces depends significantly on surface structures/texture and temperature. Many thanks goes to the coauthors of this article Aisha Okmi, Kai Xiao, Sidong Lei, Andrew Lupini, and Stephen Jesse. In addition, the help from Philip Rack and Jason Fowlkes was pivotal in fleshing out the details and models in the original article (linked above). #graphene #STEM #hydrocarbons #cleangraphene

"By leveraging physics and nature’s own “toolbox,” specifically biomolecules like proteins, Kisley aims to understand how these elements can be extracted from complex sources. The biomolecules can be used in water-based solutions and be immobilized on solid supports. Kisley will specifically be imaging how size and porosity effect the ability to separate #REEs." https://lnkd.in/dEfbEWzH

#FlameAerosol synthesis is used to create nanoparticles that serve as key ingredients in #inks and #AirFilters. While effective, this technique has limitations, including challenges with manipulating the flame, achieving precise control over the size and distribution of #nanoparticles, and cost. Two new studies, from researchers at the University at Buffalo; the U.S. Department of Energy’s Berkeley Lab, Brookhaven National Laboratory, and Lawrence Livermore National Laboratory; and the National Synchrotron Radiation Research Centre in Taiwan have addressed these shortcomings. The studies center on a unique flame aerosol system that is versatile, easy-to-use and cost-effective. In one of the studies, the system was used to create #MetalOrganicFrameworks, which are #porous #nanomaterials; in the other study, the researchers showed that the system could be used to create high-#entropy #ceramic nanomaterials.  https://lnkd.in/ec2TXiaC (Work funded by the U.S. Department of Energy (DOE)) Mark Swihart Chaochao Dun

Interesting success in physics and materials science: single-atom layer gold (2 dimensions) build https://lnkd.in/ea2w98-5