A5027204434- Electronic and Structural Properties of Oxides
- Magnetic and transport properties of perovskites and related materials
- Semiconductor materials and devices
- Catalytic Processes in Materials Science
- Ammonia Synthesis and Nitrogen Reduction
- Catalysis and Oxidation Reactions
- Advanced Battery Materials and Technologies
- Advancements in Battery Materials
- Luminescence Properties of Advanced Materials
- Advanced Battery Technologies Research
- Material Science and Thermodynamics
- Advancements in Solid Oxide Fuel Cells
- Electron and X-Ray Spectroscopy Techniques
- Transition Metal Oxide Nanomaterials
- Ga2O3 and related materials
- CO2 Reduction Techniques and Catalysts
- Advanced Condensed Matter Physics
- Surface and Thin Film Phenomena
- ZnO doping and properties
- Textile materials and evaluations
- Tea Polyphenols and Effects
University of Wisconsin–Madison
2018-2024
Princeton University
2024
The familiar work function $\mathrm{\ensuremath{\Phi}}$ (the energy barrier for an electron to move across a material's surface into the vacuum) is central vast array of and interfacial processes, thus fundamental technologies ranging from vacuum solid-state electronics catalysis. Despite this importance, multiple issues associated with varying level electrons near surfaces often obscure how being defined, measured, used. This Review clarifies definition extra care, summarizes recent...
Abstract All solid‐state batteries are desirable for a range of energy storage applications which require high density. Achieving density in battery requires the operation an dense anode with composite cathode. Pores and/or voids within solid state cathode ion‐blocking and thus control over concentration distribution pores initial electrode cycled is desirable. This study provides understanding interplay between microstructure mechanics on active material utilization cathodes composed NCM...
Solid electrolyte failure can occur through a range of different mechanisms. Electrochemical delamination at electrode and interfaces is prominent mechanism during high capacity low N/P operating conditions, filament formation prevalent rate long cycle-life deposition. Interface coherency the solid microstructure both impact ultimate degradation mode. The microstructure, described in part by density, periodicity, interconnected arrangement pores, plays role failure. Herein, we combine...
Abstract Engineering a material's work function is of central importance for many technologies and in particular electron emitters used high‐power vacuum electronics thermionic energy converters. A low surface typically achieved through unstable functional species, especially high power emitter applications. Discovering engineering new materials with intrinsic, stable functions obtainable without volatile species would mark definitive advancement the design emitters. This reports evidence...
$\mathrm{SrV}{\mathrm{O}}_{3}$ thin films with a high figure of merit for applications as transparent conductors were crystallized from amorphous layers using solid phase epitaxy (SPE). Epitaxial on $\mathrm{SrTi}{\mathrm{O}}_{3}$ SPE exhibit room-temperature resistivities low $5.2\ifmmode\times\else\texttimes\fi{}{10}^{--5}$ and $2.5\ifmmode\times\else\texttimes\fi{}{10}^{--5}\phantom{\rule{0.16em}{0ex}}\mathrm{\ensuremath{\Omega}}\phantom{\rule{0.16em}{0ex}}\mathrm{cm}$, residual...
Perovskite SrVO3 has recently been proposed as a novel electron emission cathode material. Density functional theory (DFT) calculations suggest multiple low work function surfaces, and recent experimental efforts have consistently demonstrated effective functions of ∼2.7 eV for polycrystalline samples, both results suggesting, but not directly confirming, that some fraction even lower surface is present. In this work, thermionic microscopy (ThEEM) high-field ultraviolet photoemission...
Recent experimental thermionic emission characterization measurements of the perovskite oxide SrVO3 demonstrated that low work functions can be achieved with intrinsic surface dipoles on monolithic polar perovskites, while recent density functional theory (DFT) calculations suggest many perovskites in addition to may also show function. In this investigation, we studied behavior another suggested from DFT, BaMoO3, together its related physical properties. The temperature limited current...
Our recent computational discovery of SrVO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> possessing a low work function has spurred much larger modeling effort to search for additional, new perovskite compounds with applications as thermionic electron emitting cathodes. Here, we detail our progress conducting high-throughput Density Functional Theory calculations on set ~3100 compounds. We found numerous materials which possess...
Perovskite SrVO$_3$ has recently been proposed as a novel electron emission cathode material. Density functional theory (DFT) calculations suggest multiple low work function surfaces and recent experimental efforts have consistently demonstrated effective functions of ~2.7 eV for polycrystalline samples, both results suggesting, but not directly confirming, some fraction even lower surface is present. In this work, thermionic microscopy (ThEEM) high-field ultraviolet photoemission...
This work reports improved emission performance of bulk, polycrystalline <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{SrVO_{3}}$</tex> thermionic emitters with low effective function (2.3 – 2.4 eV) and stable properties. We observed that long term vacuum annealing xmlns:xlink="http://www.w3.org/1999/xlink">$\boldsymbol{(\sim 5\ \mathrm{x}\ 10^{-10}}$</tex> torr, xmlns:xlink="http://www.w3.org/1999/xlink">$\boldsymbol{\sim 1250\...
First-principles calculations based on Density Functional Theory (DFT) previously revealed that perovskite SrVO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> is a promising candidate for thermionic emission applications. In this work, polycrystalline bulk and epitaxial thin film SrVO3 samples have been experimentally examined. Both can exhibit low work function, consistent with DFT corresponding behavior. potentially good emitter...
Work function is a key electron emission property. However, questions remain on how to unambiguously measure and interpret the work function. In this proceeding, using polycrystalline SrVO <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</inf> perovskite as an example, we clarify few issues in characterization. We show that vacuum level, which significantly affected by patch external electric fields, needs be carefully selected obtain clear...