A5028614270- Electrocatalysts for Energy Conversion
- Hydrogen Storage and Materials
- Magnetic and transport properties of perovskites and related materials
- Advanced battery technologies research
- Multiferroics and related materials
- Electrochemical Analysis and Applications
- Ferroelectric and Piezoelectric Materials
- Iron oxide chemistry and applications
- Magnetic properties of thin films
- Catalytic Processes in Materials Science
- Advancements in Battery Materials
- Advanced Condensed Matter Physics
- CO2 Reduction Techniques and Catalysts
- Advanced oxidation water treatment
- Advanced Memory and Neural Computing
- Electronic and Structural Properties of Oxides
- Fuel Cells and Related Materials
- Machine Learning in Materials Science
- Non-Destructive Testing Techniques
- Ammonia Synthesis and Nitrogen Reduction
- Supercapacitor Materials and Fabrication
- Transition Metal Oxide Nanomaterials
- Advanced Battery Materials and Technologies
- Magnetic Properties and Applications
- Conducting polymers and applications
Massachusetts Institute of Technology
2020-2024
Auburn University
2023-2024
University of Nebraska–Lincoln
2016-2020
St Petersburg University
2011-2020
A strategy to modulate the electrocatalytic activity of copper toward CO2 reduction involving adsorption acrylamide, acrylic acid, and allylamine polymers is presented. Modification electrodeposited foam with poly(acrylamide) leads a significant enhancement in faradaic efficiency for ethylene from 13% (unmodified foam) 26% at −0.96 V vs RHE, whereas methane yield unaffected. Effects crystalline phase distribution oxide phases are ruled out as source through XPS situ XRD analysis. DFT...
Physical neural networks made of analog resistive switching processors are promising platforms for computing. State-of-the-art switches rely on either conductive filament formation or phase change. These processes suffer from poor reproducibility high energy consumption, respectively. Herein, we demonstrate the behavior an alternative synapse design that relies a deterministic charge-controlled mechanism, modulated electrochemically in solid-state. The device operates by shuffling smallest...
RuO2 is one of the most active electrocatalysts toward oxygen evolution reaction (OER), but it suffers from rapid dissolution in electrochemical environments. It also established experimentally that corrosion metal oxides can, fact, promote catalytic activity for OER owing to formation a surface hydrous amorphous layer. However, mechanistic interplay between and across metal-oxide catalysts what degree these two processes are correlated still debated. Herein, we employ ab initio molecular...
The effect of a variety intrinsic defects and defect clusters in bulk thin films SrTiO$_3$ on ferroelectric polarization switching mechanism is investigated by means density-functional-theory (DFT) based calculations the Berry phase approach. Our results show that both titanium Ti$_\mathrm{Sr}^{\bullet \bullet}$ strontium Sr$_\mathrm{Ti}^{"}$ antisite induce SrTiO$_3$, with causing more pronounced spontaneous higher activation barriers reversal than Sr$_\mathrm{Ti}^{"}$. presence oxygen...
Abstract Single-phase multiferroic materials that allow the coexistence of ferroelectric and magnetic ordering above room temperature are highly desirable, motivating an ongoing search for mechanisms unconventional ferroelectricity in oxides. Here, we report antisite defect mechanism epitaxial thin films yttrium orthoferrite, YFeO 3 , a perovskite-structured canted antiferromagnet. A combination piezoresponse force microscopy, atomically resolved elemental mapping with aberration corrected...
MXenes are versatile 2D materials demonstrating outstanding electrochemical and physical properties, but their practical use is limited, because of fast degradation in an aqueous environment. To prevent the MXenes, it essential to understand atomistic details reaction identify active sites. In this letter, we provided a computational analysis processes at interface between MXene basal planes water using enhanced sampling ab initio molecular dynamics simulations symbolic regression analysis....
Abstract Incorporating hydrogen into complex oxides holds promise for discovering exotic phenomena and novel functionalities by promoting couplings between ion lattice/charge/spin/orbital degrees of freedom. Here, electrolyte gating‐driven hydrogenation is investigated in epitaxial brownmillerite SrFeO 2.5 thin films which the hydrogenation‐induced lattice distortion qualitatively different from its counterpart SrCoO . The achievable expansion hydrogenated weaker than primarily occurs along...
Recent experimental results have demonstrated ferroelectricity in thin films of SrTiO_{3} induced by antisite Ti_{Sr} defects. This opens a possibility to use as barrier layer ferroelectric tunnel junctions (FTJs)-emerging electronic devices promising for applications nanoelectronics. Here using density functional theory combined with quantum-transport calculations applied prototypical Pt/SrTiO_{3}/Pt FTJ, we demonstrate that the localized in-gap energy states produced defects are...
Dissolution of redox-active metal oxides plays a key role in variety phenomena, including (photo)electrocatalysis, degradation battery materials, corrosion oxides, and biogeochemical cycling metals natural environments. Despite its widespread significance, mechanisms metal-oxide dissolution remain poorly understood on the atomistic level. This study is aimed at elucidating long-standing problem iron from Fe(III)-oxide, complex process involving coupled hydrolysis, surface protonation,...
Vanadium redox flow batteries (VRFBs) represent a promising solution to grid-scale energy storage, and understanding the reactivity of electrode materials is crucial for improving power density VRFBs. However, atomistic details about interactions between vanadium ions surfaces in aqueous electrolytes are still lacking. Here, we examine basal (0001) edge (112[combining macron]0) graphite facets with water V2+/V3+ species at 300 K employing Car-Parrinello molecular dynamics (CPMD) coupled...
Iridium-based materials are considered as state-of-the-art electrocatalysts for oxygen evolution reaction (OER), however, their stability and catalytic activity greatly depend on surface-state changes induced by electrochemical cycling. To better understand the behavior of low-index Ir surfaces in an environment, we perform a systematic thermodynamic analysis means density functional theory (DFT) calculations. On basis computed surface energies (111), (110) (100) facets function applied...
Irreversible dissolution of transition metals (TMs) from cathode materials in lithium-ion batteries (LIBs) represents a serious challenge for the application high-energy-density LIBs. Despite substantial improvements achieved by Ni doping LiMn2O4 spinel, promising high-voltage LiNi0.5Mn1.5O4 (LNMO) material still suffers loss electro-active (Mn and Ni). This process contributes to formation solid-electrolyte interfaces capacity severely limiting battery life cycle. Here, we combine static ab...
Redox flow batteries (RFBs) are promising electrochemical energy storage systems, for which development is impeded by a poor understanding of redox reactions occurring at electrode/electrolyte interfaces. Even the conventional all-vanadium RFB chemistry employing V2+/V3+ and VO2+/VO2+ couples, there still no consensus about reaction mechanism, electrode active sites, rate-determining step. Herein, we perform Car-Parrinello molecular dynamics-based metadynamics simulations to unravel...
Strontium titanate (SrTiO3) is the "silicon" in emerging field of oxide electronics. While bulk properties this material have been studied for decades, new unexpected phenomena recently discovered at nanoscale, when SrTiO3 forms an ultrathin film or atomically sharp interface with other materials. One striking discoveries room-temperature ferroelectricity strain-free films driven by TiSr antisite defects, which generate a local dipole moment polarizing surrounding nanoregion. Here, we...
Compared to the studies of new electrolyte and electrode chemistries aimed push energy power density battery systems, investigations self-discharge reactions contributing capacity fading are still very limited, especially at molecular level. Herein, we present a computational study oxidation–reduction between vanadium ions in solution leading due crossover species through membrane all-vanadium redox flow batteries (RFB). By utilizing Car–Parrinello dynamics (CPMD) based metadynamics...
Ionic control of magnetic properties, dubbed magneto-ionics, has gained much attention in recent years due to the sizable effects that can be induced by electrically controlled ion motion. Here we assess mechanism which hydrogen affects anisotropy representative ferromagnetic/nonmagnetic metal layers. We take Co/Pd film as a model system is widely used spintronics. First-principles calculations demonstrate moment switched ${90}^{\ensuremath{\circ}}$ via insertion at interface. This results...
Cation lattice flexibility and covalent bond lengths serve as good physical descriptors of proton conduction in solid acids enable the discovery promising conductors beyond traditional chemistries.
A molecular level understanding of the properties electroactive vanadium species in aqueous solution is crucial for enhancing performance redox flow batteries (RFB). Here, we employ Car-Parrinello dynamics (CPMD) simulations based on density functional theory to investigate hydration structures, first hydrolysis reaction and diffusion V$^{2+}$, V$^{3+}$, VO$^{2+}$, VO$_2^+$ ions at 300 K. The results indicate that shell both V$^{2+}$ V$^{3+}$ contains six water molecules, while VO$^{2+}$...
Atomic-scale understanding of CO2 adsorption and reactivity on TiO2 is important for the development new catalysts conversion with improved efficiency selectivity. Here, we employ Car–Parrinello molecular dynamics combined metadynamics simulations to explore interaction rutile TiO2(110) surface explicitly treating water solution at 300 K. We focus competitive H2O, as well kinetics CO bicarbonate (HCO3–) formation. Our results show that configurations possible reaction pathways are greatly...