A5086383928- CO2 Reduction Techniques and Catalysts
- Boron and Carbon Nanomaterials Research
- Electrocatalysts for Energy Conversion
- Rare-earth and actinide compounds
- Advanced Photocatalysis Techniques
- Electrochemical Analysis and Applications
- Ionic liquids properties and applications
- Metal and Thin Film Mechanics
- MXene and MAX Phase Materials
- Advanced ceramic materials synthesis
- Advanced Electron Microscopy Techniques and Applications
- Electronic and Structural Properties of Oxides
- Quantum Dots Synthesis And Properties
- Superconductivity in MgB2 and Alloys
- X-ray Spectroscopy and Fluorescence Analysis
- Copper-based nanomaterials and applications
- Semiconductor materials and interfaces
- Inorganic Chemistry and Materials
- Advanced battery technologies research
- Radical Photochemical Reactions
- Nanowire Synthesis and Applications
- Advanced Materials Characterization Techniques
- Advanced Thermoelectric Materials and Devices
- Gold and Silver Nanoparticles Synthesis and Applications
- High-pressure geophysics and materials
University of California, Berkeley
2019-2024
Lawrence Berkeley National Laboratory
2016-2024
University of California, Los Angeles
2017-2024
nLIGHT (United States)
2023
Université Paris-Sud
2019
University of Rochester
2019
EPF - École d'ingénieurs
2019
University of California System
2018
Los Angeles City College
2018
The development of photoelectrochemical systems for converting CO2 into chemical feedstocks offers an attractive strategy clean energy storage by directly utilizing solar energy, but selectivity and stability these have thus been limited. Here, we interface silicon nanowire (SiNW) photocathodes with a copper nanoparticle (CuNP) ensemble to drive efficient conversion multicarbon products. This integrated system enables CO2-to-C2H4 faradaic efficiency approaching 25% partial current densities...
Artificial photosynthesis offers a route to producing clean fuel energy. However, the large thermodynamic requirement for water splitting along with corresponding sluggish kinetics oxygen evolution reaction (OER) limits its current practical application. Here, we offer an alternative approach by replacing OER glycerol oxidation (GOR) value-added chemicals. By using Si photoanode, low GOR onset potential of -0.05 V vs RHE and photocurrent density 10 mA/cm2 at 0.5 can be reached. Coupled...
Understanding the chemical environment and interparticle dynamics of nanoparticle electrocatalysts under operating conditions offers valuable insights into tuning their activity selectivity. This is particularly important to design Cu nanocatalysts for CO2 electroreduction due dynamic nature bias. Here, we have developed operando electrochemical resonant soft X-ray scattering (EC-RSoXS) probe identity active sites during structural transformation (NP) ensembles through 1 μm thick...
Photocathodic conversion of NAD+ to NADH cofactor is a promising platform for activating redox biological catalysts and enzymatic synthesis using renewable solar energy. However, many photocathodes suffer from low photovoltage, consequently requiring high cathodic bias production. Here, we report an n+p-type silicon nanowire (n+p-SiNW) photocathode having photovoltage 435 mV drive energy-efficient The enhanced band bending at the n+/p interface accounts which conduces benchmark onset...
SignificanceThe electroconversion of CO
The design and synthesis of nanocatalysts with well-defined sizes, compositions, structures have revolutionized our accessibility to tunable catalyst activity selectivity for a variety energy-related electrochemical reactions. Nonetheless, establishing structure-(re)activity correlations requires the understanding dynamic evolution pristine identification their active states under operating conditions. We previously communicated operando observation Cu evolving into metallic nanograins CO2...
Tungsten tetraboride is an inexpensive, superhard material easily prepared at ambient pressure. Unfortunately, there are relatively few compounds in existence that crystallize the same structure as tungsten tetraboride. Furthermore, lack of data phase space limits discovery any new also possess high incompressibility and a three-dimensional boron network withstands shear. Thus, focus work here to chemically probe range thermodynamically stable with respect both transition metal content....
Tungsten tetraboride alloys with Y, Sc, Gd, Tb, Dy, Ho, and Er were prepared by arc-melting investigated for their thermal stability mechanical properties. The phase composition purity confirmed powder X-ray diffraction (PXRD) energy dispersive spectroscopy (EDS). In all cases, except a change to "dendritic" morphology was observed. For the metal boride boron grains became smaller; however, no patterning This shows that tuning of WB4 transition metals lanthanides results in modification...
Lanthanum hexaboride (LaB6) is known for its hardness, mechanical strength, thermionic emission, and strong plasmonic properties. However, given the lack of colloidal synthetic methods to access this material, very little understood about physical properties on nanoscale. Recently, a new moderate-temperature technique was developed directly synthesize LaB6 nanoparticles [Mattox et al. Chem. Mater. 2015, 27, 6620]. We report influence nanoparticle size structural vibrational using combination...
Lanthanum hexaboride (LaB₆) has become a material of intense interest in recent years due to its low work function, thermal stability and intriguing optical properties. LaB₆ is also semiconductor plasmonic with the ability support strong plasmon modes. Some these modes uniquely stretch into infrared, allowing absorb around 1000 nm, which great window industry. It well known that can be tuned by controlling particle size shape. In this work, we explore options available further tune...
The metal borides: YReB4, YCrB4 (YCrB4 structural type), Y2ReB6, Sc2ReB6 (Y2ReB6), Y3ReB7, Y3MoB7, and Y3WB7 (Y3ReB7), YMo3B7 (YMo3B7) types, their solid-solutions: YRe1–xCrxB4, Y1–xScxCrB4, Y2–2xSc2xReB6, Y2Re1–xCrxB6, YMo1–xWxB7 were analyzed using powder X-ray diffraction energy-dispersive spectroscopy, studied for mechanical properties. These borides possess unique crystal structures, not found in any other type of alternating boron layers with being arranged 5-, 6-, 7-member rings...
Single-phase metal dodecaboride solid solutions, Zr0.5Y0.5B12 and Zr0.5U0.5B12, were prepared by arc melting from pure elements. The phase purity composition established powder X-ray diffraction (PXRD), energy-dispersive spectroscopy (EDS), photoelectron (XPS), 10B 11B solid-state nuclear magnetic resonance (NMR) spectroscopy. effects of carbon addition to Zr1–xYxB12 studied it was found that causes fast cooling as a result rapid nucleation grains, well "templating" patterning the surface...
Electrochemically derived multicarbon products are a golden target for valorization of captured carbon dioxide due to the potential turning waste product into useful commodity chemicals with renewable energy sources. As tantalizing approach toward their synthesis, formose reaction utilizes catalytic condensation formaldehyde generate carbohydrates. While sustainable artificial carbohydrate production through electrochemical generation is desirable, date, it has not been fully realized. Here,...
Samples of metal borides with a nominal composition ((M1)(1-x-z)(M2)(x)(M3)(z)) : 20B (M1, M2 and M3 = Zr, Y, Hf Gd) were prepared by arc-melting studied for phase (using powder X-ray diffraction (PXRD) energy dispersive spectroscopy (EDS)) mechanical properties (Vickers hardness). Ternary dodecaboride phases successfully synthesized the majority compositions, including stabilization two high-pressure (6.5 GPa) (cubic-UB12 structure), HfB12 GdB12, in (Zr1-x-zHfxGdz) (Y1-x-zHfxGdz) alloy...
Lanthanum hexaboride (LaB6) is notable for its thermionic emission and mechanical strength being explored potential applications in IR-absorbing photovoltaic cells thermally insulating window coatings. Previous studies have not investigated how the properties of LaB6 change on nanoscale. Despite interest tunable plasmonic nanocrystalline LaB6, been limited due to challenges synthesis phase-pure, size-controlled, high-purity nanocrystals without high temperatures or pressures. Here, we...
Alloys of tungsten tetraboride (WB4) with the addition C and Si were prepared by arc-melting constituent elements. The phase purity was established powder X-ray diffraction (PXRD) surface morphology scanning electron microscopy (SEM) analysis. Vickers hardness measurements showed enhancement for alloys a nominal composition (W0.98Si0.02):11.6B (W0.95C0.05):11.6B 52.2 ± 3.0 50.5 2.5 GPa, respectively, compared to 41.2 1.4 GPa pure WB4. (W0.92Zr0.08):11.6B determined in previous work have 55.9...