The Synthesis of Amphiphilic Luminescent Graphene Quantum Dot and Its Application in Miniemulsion Polymerization

Although emulsion applications of microscale graphene sheets have attracted much attention recently, nanoscale graphene platelets, namely, graphene quantum dots (GQDs), have been rarely explored in interface science. In this work, we study the interfacial behaviors and emulsion phase diagrams of hydrophobic-functionalized graphene quantum dots (C18-GQDs). Distinctive from pristine graphene quantum dots (p-GQDs), C18-GQDs show several interesting surface-active properties including high emulsification efficiency in stabilizing dodecane-in-water emulsions. We then utilize the C18-GQDs as surfactants in miniemulsion polymerization of styrene, achieving uniform and relatively small polystyrene nanospheres. The high emulsification efficiency, low production cost, uniform morphology, intriguing photoluminescence, and extraordinary stability render C18-GQDs an attractive alternative in surfactant applications

Structured illumination with thermal imaging (SI-TI): A dynamically reconfigurable metrology for parallelized thermal transport characterization

The recent push for the "materials by design"paradigm requires synergistic integration of scalable computation, synthesis, and characterization. Among these, techniques for efficient measurement of thermal transport can be a bottleneck limiting the experimental database size, especially for diverse materials with a range of roughness, porosity, and anisotropy. Traditional contact thermal measurements have challenges with throughput and the lack of spatially resolvable property mapping, while non-contact pump-probe laser methods generally need mirror smooth sample surfaces and also require serial raster scanning to achieve property mapping. Here, we present structured illumination with thermal imaging (SI-TI), a new thermal characterization tool based on parallelized all-optical heating and thermometry. Experiments on representative dense and porous bulk materials as well as a 3D printed thermoelectric thick film (∼50 μm) demonstrate that SI-TI (1) enables paralleled measurement of multiple regions and samples without raster scanning; (2) can dynamically adjust the heating pattern purely in software, to optimize the measurement sensitivity in different directions for anisotropic materials; and (3) can tolerate rough (∼3 μm) and scratched sample surfaces. This work highlights a new avenue in adaptivity and throughput for thermal characterization of diverse materials

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

Nanoplate Surfactants and Liquid Crystals

Low-dimensional 2D materials, i.e., nanoplates, show exceptional properties such as high surface area/volume ratio that make these materials important for applications demanding high levels of surface/interface interactions at nanoscale. Despite significant advances of nanoplates in energy applications, the role of nanoplates in binary complex fluids (e.g., emulsions) or anisotropic fluids (e.g., liquid crystals) remains underexplored. In this dissertation, we developed various surface-engineered nanoplates and investigated their collective behaviors as colloid surfactants, liquid crystals, and active soft materials. 2D nanoplates have been synthesized for use in stabilizing oil-in-water emulsions and regulating molecular delivery systems, in which they can interact with large amounts of key molecules, allowing superior control over transport/diffusion kinetics. In addition, strongly anisotropic nanoplates have also been developed with tunable photonic bandgaps and corresponding iridescent colors across the full visible spectrum in colloidal suspensions. We envision that the control of self-assembly of 2D building blocks would enable bottom-up fabrication of emerging multifunctional soft materials for diverse applications including specialty surfactants, photonic sensors, pollutant removal, and smart delivery systems

Highly Efficient Oil-Water Separation Using Surface-Programmable Membranes

Presented at the Symposium on Soft Matter Forefronts "Contributed Talks", April 20, 2018, from 11:10 a.m.-12:00 p.m. in the Student Center Ballroom, Georgia Tech.Chairs: Volodymyr Korolovych & Blair Brettmann (Georgia Tech).Minxiang Zeng is with Texas A&M University.Runtime: 10:45 minutesThe challenge of separating emulsified oil from oil/water mixture has sparked enormous research interests in developing advanced membrane technology. One of the most crucial elements to achieve high separating efficiency lies in the design of unique interfacial properties of membranes. Herein, we present a surface-programmable membrane for separating oil-water emulsion based on contrast wetting strategy. Additionally, owing to the precise control on the surface chemistry and microstructures of membranes, the hybrid membrane not only separates the oil-water mixture with high efficiency (>99.2%), but also demonstrates versatility for multiple applications, e.g., heavy metal removal. This research opens up new opportunities in developing multifunctional membrane-based materials.Georgia Institute of Technology. College of SciencesGeorgia Institute of Technology. Institute for MaterialsGeorgia Institute of Technology. Parker H. Petit Institute for Bioengineering and BioscienceGeorgia Institute of Technology. School of Materials Science and EngineeringGeorgia Institute of Technology. School of PhysicsAmerican Physical SocietyExxon Mobil CorporationNational Science Foundation (U.S.

All-Printed MXene–Graphene Nanosheet-Based Bimodal Sensors for Simultaneous Strain and Temperature Sensing

Multifunctional sensors with integrated multiple sensing capabilities have enormous potential for in situ sensing, structural health monitoring, and wearable applications. However, the fabrication of multimodal sensors typically involves complex processing steps, which limit the choices of materials and device form factors. Here, an aerosol jet printed flexible bimodal sensor is demonstrated by using graphene and Ti3C2Tx MXene nanoinks. The sensor can detect strain by measuring a change in the AC resistive voltage while simultaneously monitoring temperature by detecting the DC Seebeck voltage across the same printed device pattern. The printed bimodal sensor not only expands the sensing capability beyond conventional single-modality sensors but also provides improved spatial resolution utilizing the microscale printed patterns. The printed temperature sensor shows a competitive thermopower output of 53.6 μV/°C with ultrahigh accuracy and stability during both steady-state and transient thermal cycling tests. The printed sensor also demonstrates excellent flexibility with negligible degradations after 1000 bending cycles. The aerosol jet printing and integration of nanomaterials open many opportunities to design and manufacture multifunctional devices for a broad range of applications

Putting a Terbium-Monometallic Cyanide Cluster into the C₈₂ Fullerene Cage: TbCN@<i>C</i>₂(5)‑C₈₂

The first terbium (Tb)-monometallic cyanide clusterfullerene (CYCF), TbCN@C₈₂, has been successfully synthesized and isolated, whose molecular structure was determined unambiguously as TbCN@<i>C</i>₂(5)-C₈₂ by single crystal X-ray diffraction. The <i>C</i>₂(5)-C₈₂ isomeric cage represents a new cage capable of encapsulating a monometallic cyanide cluster. The C–N bond length within the encaged TbCN cluster is determined to be 0.94(5) Å, which is smaller by at least 0.17 Å than those of the reported C–N triplet bonds in traditional cyanide/nitrile compounds and cyano coordination complexes. An electronic configuration of [Tb³⁺(CN)⁻]²⁺@[C₈₂]^2– was proposed for TbCN@C₈₂

Pulsed Light Synthesis of High Entropy Nanocatalysts with Enhanced Catalytic Activity and Prolonged Stability for Oxygen Evolution Reaction

Abstract The ability to synthesize compositionally complex nanostructures rapidly is a key to high‐throughput functional materials discovery. In addition to being time‐consuming, a majority of conventional materials synthesis processes closely follow thermodynamics equilibria, which limit the discovery of new classes of metastable phases such as high entropy oxides (HEO). Herein, a photonic flash synthesis of HEO nanoparticles at timescales of milliseconds is demonstrated. By leveraging the abrupt heating and cooling cycles induced by a high‐power‐density xenon pulsed light, mixed transition metal salt precursors undergo rapid chemical transformations. Hence, nanoparticles form within milliseconds with a strong affinity to bind to the carbon substrate. Oxygen evolution reaction (OER) activity measurements of the synthesized nanoparticles demonstrate two orders of magnitude prolonged stability at high current densities, without noticeable decay in performance, compared to commercial IrO2 catalyst. This superior catalytic activity originates from the synergistic effect of different alloying elements mixed at a high entropic state. It is found that Cr addition influences surface activity the most by promoting higher oxidation states, favoring optimal interaction with OER intermediates. The proposed high‐throughput method opens new pathways toward developing next‐generation functional materials for various electronics, sensing, and environmental applications, in addition to renewable energy conversion