A5014508546- Fullerene Chemistry and Applications
- Graphene research and applications
- Membrane-based Ion Separation Techniques
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Synthesis and Properties of Aromatic Compounds
- Carbon Nanotubes in Composites
- Boron and Carbon Nanomaterials Research
- Supercapacitor Materials and Fabrication
- Diamond and Carbon-based Materials Research
- Fuel Cells and Related Materials
- Molecular Junctions and Nanostructures
- Carbon Dioxide Capture Technologies
- Electrocatalysts for Energy Conversion
- Advancements in Battery Materials
- Crystallography and molecular interactions
- Membrane Separation Technologies
- Organic Electronics and Photovoltaics
- Membrane Separation and Gas Transport
- Advanced Battery Materials and Technologies
- Ammonia Synthesis and Nitrogen Reduction
- Inorganic Chemistry and Materials
- Nanopore and Nanochannel Transport Studies
- Advanced Chemical Physics Studies
- Electrochemical Analysis and Applications
Lawrence Livermore National Laboratory
2016-2024
Lawrence Livermore National Security
2020
The University of Texas at El Paso
2013-2019
University of California, Davis
2016
The contamination of water resources with nitrate is a growing and significant problem. Here we report the use ultramicroporous carbon as capacitive deionization (CDI) electrode for selectively removing from an anion mixture. Through moderate activation, achieve micropore-size distribution consisting almost exclusively narrow (<1 nm) pores that are well suited adsorbing planar, weakly hydrated molecule. Cyclic voltammetry measurements reveal enhanced capacitance when compared to chloride ion...
A non-isolated pentagon rule metallic carbide clusterfullerene containing a heptagonal ring, Sc2C2@Cs(hept)-C88, was isolated from the raw soot obtained by electric arc vaporization of graphite rods packed with Sc2O3 and powder under helium atmosphere. The Sc2C2@Cs(hept)-C88 purified multistage high-performance liquid chromatography (HPLC), cocrystallized Ni-(octaethylporphyrin), characterized single-crystal X-ray diffraction. diffraction data revealed zigzag Sc2C2 unit inside an...
Abstract Improved understanding of aqueous solutions at graphitic interfaces is critical for energy storage and water desalination. However, many mechanistic details remain unclear, including how interfacial structure response are dictated by intrinsic properties solvated ions under applied voltage. In this work, we combine hybrid first-principles/continuum simulations with electrochemical measurements to investigate adsorption several alkali-metal cations the interface graphene within...
Using a purification method introduced earlier based on redox properties it was possible to isolate Sc3N@I(h)-C80 and Sc3N@D(3h)-C78 mixture of Sc3N@D(5h)-C80 Sc3N@D3-C68. Taking advantage their chemical reactivity differences, isolated from Sc3N@D3-C68 followed by further functionalization, giving rise five new methano-derivatives Sc3N@D(5h)-C80.
ABSTRACT Three compounds (1, 2, and 3) previously reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase were studied, but only fullerene derivatives 1 2 showed strong antiviral on the human CD4 + T cells. However, these did not infection by single-round vesicular stomatitis virus glycoprotein G (VSV-G)-pseudotyped viruses, indicating no effect early steps viral life cycle. In contrast, analysis VSV-G-pseudotyped produced presence compound or a complete lack...
Capacitive deionization (CDI) is a promising water desalination technology that applicable to the treatment of low-salinity brackish waters and selective removal ionic contaminants. In this work, we show by making small change in synthetic procedure hierarchical carbon aerogel monolith (HCAM) electrodes, can adjust pore-size distribution tailor selectivity, effectively switching between adsorption calcium or sodium ions. Ion selectivity was measured for mixture 5 mM NaCl 2.5 CaCl2. For low...
The electrocatalytic properties of some endohedral fullerenes for hydrogen evolution reactions (HER) were recently predicted by DFT calculations. Nonetheless, the experimental catalytic performance under realistic electrochemical environments these 0D-nanomaterials have not been explored. Here, first time, we disclose HER behavior seven M3N@2n (2n = 68, 78, and 80) (Gd3N@Ih(7)-C80, Y3N@Ih(7)-C80, Lu3N@Ih(7)-C80, Sc3N@Ih(7)-C80, Sc3N@D5h(6)-C80, Sc3N@D3h(5)-C78, Sc3N@D3(6140)-C68) using a...
The synthesis, isolation, and characterization of a new endohedral fullerene, Sc2C88, is reported. Characterization by single crystal X-ray diffraction revealed that it the carbide Sc2C2@C(2v)(9)-C86 with planar, twisted Sc2C2 unit inside previously unseen C(2v)(9)-C86 fullerene cage.
The regioselective synthesis of easily isolable pure bismethano derivatives C60 and C70 with high steric congestion is described using 1,3-dibenzoylpropane bis-p-toluenesulfonyl hydrazone as the addend precursor. When addition occurs at two [6,6] ring junctions within same hexagon, bisadducts mirror symmetry are obtained for both C70. [5,6] in C60, a symmetrical adduct formed, which readily undergoes photo-oxygenation opening to yield fullerene hole cage. In this work, we also propose simple...
A regiospecific bis-adduct of C70 with anthracene was prepared unusually high yield (68%) by the Diels-Alder reaction in absence solvent (melt). The structure an unexpected 12 o'clock isomer, as determined single crystal X-ray diffraction, thermal gravimetric analysis (TGA) and spectroscopy.
Anion exchange membranes (AEMs) offer a cost-effective alternative to proton as alkaline fuel cells and electrolyzers permit the use of non-platinum group electrodes components. Despite continued progress, operational lifetime stability these limit widespread adoption AEM-based electrochemical technologies. This study presents flexible easily implemented ultraviolet (UV)-initiated nitrene-based cross-linking method which uses small, facile organic azide precursor. As proof concept, we...
Abstract In this work, the Bingel–Hirsch addition of diethylbromomalonate to all non‐equivalent bonds Sc 3 N@ D 3h ‐C 78 was studied using density functional theory calculations. The regioselectivities observed computationally allowed proposal a set rules, predictive aromaticity criteria (PAC), identify most reactive given endohedral metallofullerene based on simple evaluation cage structure. predictions PAC are fully confirmed by both computational and experimental exploration reaction 5h...
Cage‐cluster complementarity is of crucial importance in determining the sizes and structures, as well properties endohedral fullerenes. The encapsulated atoms or clusters, which are typically a positively charged state, irreversibly, mechanically, electrostatically trapped inside negatively cages. These rather exotic compounds exhibit exquisitely complementary between their components. Here, we present short overview to show that size shape specific structures formed, presence electrostatic...
In this work, we briefly report some attempts to control regioisomeric bisadditions on Sc3N@Ih-C80 and Lu3N@Ih-C80 using the tether-controlled multifunctionalization method. We then describe use of independent (nontethered) bis-1,3-dipolar cycloaddition reactions characterization 5 new bisadducts, 3 for Sc3N@C80 2 Lu3N@C80, which have never been reported before. Unexpectedly remarkably, 4 these compounds exhibit relatively high symmetry bisadducts are first examples intrinsically chiral...
Amine-based adsorbents are promising for direct air capture of CO2 , yet oxidative degradation remains a key unmitigated risk hindering wide-scale deployment. Borrowing wisdom from the basic auto-oxidation scheme, insights gained into underlying mechanisms polyamines by quantum chemical, advanced sampling simulations, adsorbent synthesis, and accelerated experiments. The reaction kinetics contrasted with that typical aliphatic polymers they elucidate first time critical role aminoalkyl...
Porous ceramic materials have a wide range of potential applications for which controlling the structure across multiple length scales is desirable. Additive manufacturing (AM) porous ceramics therefore interest design flexibility. Here, ink compatible with 2 AM techniques, projection microstereolithography (PμSL) and direct write (DIW), was formulated demonstrated printed parts controllable feature sizes as well nanoporosity resulting from partial sintering. A diacrylate polymer mixed 3%...
Newcomers on the scene: The modification of endohedral metallofullerenes with an Ih-C80 cage by cyclopropanation-type addition reactions generally yields [6,6] methanofullerene adducts. Now [5,6]-open methanofullerenes Ih-C80-derived have been synthesized, as confirmed X-ray crystallography, under relatively mild, stoichiometric conditions along corresponding [6,6]-open derivatives in good yields.
Abstract Based on the different oxidation potentials of endohedral fullerenes Sc 3 N@C 80 I h and D 5 78 , an efficient useful method that avoids HPLC has been developed for their separation. Selective chemical N@ ‐C isomer by using acetylferrocenium salt [Fe(COCH C H 4 )Cp] + followed column chromatographic separation reduction with CH SNa resulted in isolation pure a mixture 68 .
Bis ‐functionalized fullerenes have resulted in very effective acceptors organic photovoltaic solar cells. Here we present a short overview of specific and recently reported pure bis ‐adduct regioisomers C 60 using tethers, few recent examples ‐adducts 70 finally endohedral cluster fullerenes. We also discuss the unexpected reactivity differences empty (C ) compared with those trimetallic nitride (M 3 N@ I h ‐C 80 , M = Sc, Lu) towards tethered‐ ‐addition reactions. Finally, describe...
Understanding and controlling the electrical response at a complex electrode–electrolyte interface is key to development of next-generation supercapacitors other electrochemical devices. In this work, we apply theoretical framework based on effective screening medium reference interaction site model explore role double-layer (EDL) formation its interplay with quantum capacitance in graphene-based supercapacitors. addition pristine graphene, investigate novel C60-modified graphene...
The synthesis and characterization of a family [60]fullerocurcuminoids obtained via Bingel reactions is reported. new C60 derivatives include curcumin curcuminoids with variety end groups. Preliminary biological experiments show the potential activity compound containing addend, which exhibits moderate anti-HIV-1 radical scavenger properties, but no anti-cancer activity. In addition, fullerocurcuminoids exhibit HOMO/LUMO energy levels that are reasonably matched those perovskites when they...