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Results for “multifunctionality”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Green Electrode Processing Enabled by Fluoro-Free Multifunctional Binders for Lithium-Ion Batteries

The eco-friendly processing of conjugated polymer binder for lithium-ion batteries demands improved polymer solubility by introducing functional moieties, while this strategy will concurrently sacrifice polymer conductivity. Employing the polyfluorene-based binder poly(2,7-9,9 (di(oxy-2,5,8-trioxadecane))fluorene) (PFO), soluble in water-ethanol mixtures, a novel approach is presented to solve this trade-off, which features integration of aqueous solution processing with subsequent controlled thermal-induced cleavage of solubilizing side chains, to produce hierarchically ordered structures (HOS). The thermal processing can enhance the intermolecular π–π stacking of polyfluorene backbone for better electrochemical performance. Notably, HOS-PFO demonstrated a substantial 6–7 orders of magnitude enhancement in electronic conductivity, showcasing its potential as a functional binder for lithium-ion batteries. As an illustration, HOS-PFO protected SiOx anodes, utilizing in situ side chain decomposition of PFO surrounding SiOx particles after aqueous processing are fabricated. HOS-PFO contributed to the stable cycling and high-capacity retention of practical SiOx anodes (3.0 mAh cm -2 ), without the use of any conducting carbon additives or fluorinated electrolyte additives. It is proposed that this technique represents a universal approach for fabricating electrodes with conjugated polymer binders from aqueous solutions without compromising conductivity.

25 ENERGY STORAGE↗
DOE OSTI2017

Multifunctional Optoelectronic-Spintronic Device Based on Hybrid Organometal Trihalide Perovskites

A novel “hybrid” optoelectronic–spintronic (O-S) device that contains an organometal trihalide perovskite (OTP)-based solar cell or light-emitting diode coupled to an inorganic spin valve is presented. The synergy between the OTP and spin valve components results in two new functionalities: nonlinear magnetophotoconductivity and hysteretic magnetoelectroluminescence.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Multifunctional Utilization of Pitch-Coated Carbon Fibers in Lithium-Based Rechargeable Batteries

This work reports carbon fibers as an electrode material and current collector for dual-carbon and lithium-ion batteries. Here, fully graphitic and semigraphitic carbon fibers undergo anion intercalation beyond 4.5 V versus Li/Li + . Symmetric dual-carbon full cells using a pitch-coated fully graphitic carbon fiber mat as both cathode and anode delivers an energy-density of 276 and 322 Wh kg -1 at 342 W kg -1 power density in the voltage range of 3.0–5.0 and 3.0–5.2 V, respectively. On the other hand, nongraphitic carbon fibers do not exhibit anion intercalation up to 5.2 V and can be used as a current collector. They also possess a larger number of Li + storage sites in their randomly oriented microstructure when used as an anode. A lithium-ion full cell with double carbon-coated C-LiFePO 4 loaded on nongraphitic carbon fiber as a cathode and pitch-coated nongraphitic carbon fiber as an anode exhibits 202.6 and 75.2 Wh kg -1 energy density at power densities of 46.75 W kg -1 and 11.7 kW kg -1 , respectively in 2.0–3.5 V range. This pitch-coated carbon fiber-based battery configuration eliminates the need for metal foils and costly fluorinated binders, lowers overall weight of the cell, and is capable of sustaining mechanical stress and thermal shock.

PF6− intercalation↗
DOE OSTI2018

Novel multidomain, multifunctional glycoside hydrolases from highly lignocellulolytic Caldicellulosiruptor species

Biological hydrolysis of microcrystalline cellulose is an uncommon feature in the microbial world, especially among bacteria and archaea growing optimally above 70 degrees C (the so-called extreme thermophiles). In fact, among this group only certain species in the genus Caldicellulosiruptor are capable of rapid and extensive cellulose degradation. Four novel multidomain glycoside hydrolases (GHs) from Caldicellulosiruptor morganii and Caldicellulosiruptor danielii were produced recombinantly in Caldicellulosiruptor bescii and characterized. These GHs are structurally organized with two or three catalytic domains flanking carbohydrate binding modules from Family 3. Collectively, these enzymes represent GH families 5, 9, 10, 12, 44, 48, and 74, and hydrolyze crystalline cellulose, glucan, xylan, and mannan, the primary carbohydrates in plant biomass. Degradation of microcrystalline cellulose by cocktails of GHs from three Caldicellulosiruptor species demonstrated that synergistic interactions enable mixtures of multiple enzymes to outperform single enzymes, suggesting a community mode of action for lignocellulose utilization in thermal environments.

09 BIOMASS FUELS↗
DOE OSTI2020

Large-Scale Plasmonic Hybrid Framework with Built-In Nanohole Array as Multifunctional Optical Sensing Platforms

Light coupling with patterned subwavelength hole arrays induces enhanced transmission supported by the strong surface plasmon mode. In this work, a nanostructured plasmonic framework with vertically built-in nanohole arrays at deep-subwavelength scale (6 nm) is demonstrated using a two-step fabrication method. The nanohole arrays are formed first by the growth of a high-quality two-phase (i.e., Au–TiN) vertically aligned nanocomposite template, followed by selective wet-etching of the metal (Au). Such a plasmonic nanohole film owns high epitaxial quality with large surface coverage and the structure can be tailored as either fully etched or half-way etched nanoholes via careful control of the etching process. The chemically inert and plasmonic TiN plays a role in maintaining sharp hole boundary and preventing lattice distortion. Optical properties such as enhanced transmittance and anisotropic dielectric function in the visible regime are demonstrated. Numerical simulation suggests an extended surface plasmon mode and strong field enhancement at the hole edges. Furthermore, two demonstrations, including the enhanced and modulated photoluminescence by surface coupling with 2D perovskite nanoplates and the refractive index sensing by infiltrating immersion liquids, suggest the great potential of such plasmonic nanohole array for reusable surface plasmon-enhanced sensing applications.

42 ENGINEERING↗
DOE OSTI2020

Organometallic Synthesis of Bimetallic Cobalt‐Rhodium Nanoparticles in Supported Ionic Liquid Phases (Co x Rh 100− x @SILP) as Catalysts for the Selective Hydrogenation of Multifunctional Aromatic Substrates

Abstract The synthesis, characterization, and catalytic properties of bimetallic cobalt‐rhodium nanoparticles of defined Co:Rh ratios immobilized in an imidazolium‐based supported ionic liquid phase (Co x Rh 100− x @SILP) are described. Following an organometallic approach, precise control of the Co:Rh ratios is accomplished. Electron microscopy and X‐ray absorption spectroscopy confirm the formation of small, well‐dispersed, and homogeneously alloyed zero‐valent bimetallic nanoparticles in all investigated materials. Benzylideneacetone and various bicyclic heteroaromatics are used as chemical probes to investigate the hydrogenation performances of the Co x Rh 100− x @SILP materials. The Co:Rh ratio of the nanoparticles is found to have a critical influence on observed activity and selectivity, with clear synergistic effects arising from the combination of the noble metal and its 3d congener. In particular, the ability of Co x Rh 100− x @SILP catalysts to hydrogenate 6‐membered aromatic rings is found to experience a remarkable sharp switch in a narrow composition range between Co 25 Rh 75 (full ring hydrogenation) and Co 30 Rh 70 (no ring hydrogenation).

Rengshausen, Simon↗
DOE OSTI2019

Magnetic Mesocellular Foam Functionalized by Curcumin for Potential Multifunctional Therapeutics

The study investigates curcumin/SPIONs hybridized mesocellular foam type silica for potential dual purpose of drug delivery (curcumin) and magnetic resonance imaging. Magnetization capability and curcumin release was assessed for different structured silica such as spherical silica (Q-10), Si-MCM-41, Si-SBA-16, mesocellular foam (MSU-Foam), Si-KIT-6, ULPFDU-12, and silicalite. The phase, textural, and morphological variation was systematically scrutinized using various physico-chemical techniques. Ten weight percent SPIONs loading was found to generate magnetically active SPIONs in the following order: Q-10 (1.44 emu/g) > SBA-16 (0.80 emu/g) > MSU-Foam (0.24 emu/g) > Si-MCM-41 (0.07 emu/g) > Si-KIT-6 (0.07 emu/g) > silicalite (0.08 emu/g), respectively. The iron oxide dispersion, specific surface area, and porosity play a major role in various structured silicas. MSU-Foam with wormhole structure showed highest specific surface area occupation of SPIONs (73%). The presence of interconnected porosity of foam tends to generate external agglomeration of SPIONs (7–18 nm) at the pore surface contributing to expansion of pore sizes from 16.4 to 40.2 nm. The SPIONs over spherical micron-sized silica Q-10 showed the formation of large nanoclusters (10–25 nm). Thirty to 390 μg/ml of curcumin was loaded over silica and SPIONs/silica structured hybrid, and drug release was studied at pH 5.6 for 72 h. SPIONs/MSU-Foam with less magnetization showed the highest cumulative curcumin release (53.2%), while Q-10 spherical silica with high magnetization property showed less cumulative release of curcumin (12%).

77 NANOSCIENCE AND NANOTECHNOLOGY↗
DOE OSTI2021

Multifunctional Fibroblasts Enhanced via Thermal and Freeze-Drying Post-treatments of Aligned Electrospun Nanofiber Membranes

Parallel fibrous scaffolds play a critical role in controlling the morphology of cells to be more natural and biologically inspired. Among popular tissue engineering materials, poly(2-hydroxyethyl methacrylate) (pHEMA) has been widely investigated in conventional forms due to its biocompatibility, low toxicity, and hydrophilicity. However, the swelling of pHEMA in water remains a major concern. To address this issue, randomly oriented and aligned as-spun pHEMA nanofibrous scaffolds were first fabricated at speeds of 300 and 2000 rpm in this study, which were then post-treated using either a thermal or a freeze-drying method. In cell assays, human dermal fibroblasts (HDFs) adhered to the freeze-drying treated substrates at a significantly faster rate, whereas they had a higher cell growth rate on thermally-treated substrates. Results indicated that the structural properties of pHEMA nanofibrous scaffolds and subsequent cellular behaviors were largely dependent on post-treatment methods. Moreover, this study suggests that aligned pHEMA nanofibrous substrates tended to induce regular fibroblast orientation and unidirectionally oriented actin cytoskeletons over random pHEMA nanofibrous substrates. Such information has predictive power and provides insights into promising post-treatment methods for improving the properties of aligned pHEMA scaffolds for numerous tissue engineering applications.

36 MATERIALS SCIENCE↗