Vitalie Stavila

Vitalie Stavila, Ph.D.

 

Stavila.jpg

Principal Member of the Technical Staff
Energy Nanomaterials Department
PO Box 969 MS 9161, Livermore, CA 94551
Phone:  (925) 294-3059 
Email:  vnstavi@sandia.gov
Download CV

Background

Our research focuses on addressing key materials science challenges related to the development of next-generation materials for renewable energy harvesting and storage. A central theme is the rational design of new materials by changing the chemical composition, the arrangement of the atoms or molecules in crystalline or amorphous configurations, and the size, shape, and orientation of nanoparticles, thin films, and crystals. A significant focus is on elucidating fundamental transport phenomena on the nanoscale, in particular, ion and electron transfer across nanointerfaces. Using this knowledge, we seek to contribute to the development of alternative energy solutions and materials to address the many challenging environmental issues facing society today. This includes the discovery of nanoscale materials for applications in hydrogen fuel cells, solid-state batteries, neuromorphic computing, catalysis, and chemical sensing. We use a range of physical methods to characterize our materials comprehensively, including X-ray and neutron scattering, Rietveld refinement and single-crystal X-ray crystallography. In our research we widely employ data science and machine learning to reveal new structure-property-function relationships.

Education

2002    PhD, Chemistry, State University of Moldova, Chisinau, Moldova

Research Interests

Hydrogen storage in metal hydrides

Hydrogen provides multiple advantages as an energy carrier, particularly when used in hydrogen polymer electrolyte membrane fuel cells. It is non-toxic, produces zero emissions at the point of use, and enables high efficiency conversion devices such as hydrogen fuel cells. Metal hydrides are promising solid-state hydrogen storage media, with record-high gravimetric and volumetric hydrogen densities. One of the most elegant and promising storage methods is through reversible metal hydrides, which can release hydrogen endothermically upon mild heating and absorb it exothermically when pressurized with hydrogen gas. Nano_picture_stavila.jpg Our research in this area is geared towards developing a foundational understanding of the phenomena that govern hydrogen uptake and release in metal hydrides. In particular, we are interested in understanding the effects of nanointerfaces that develop in materials upon cycling, and how they affect the macroscopic material properties.

Metal-Organic Frameworks for device applications

Metal-Organic Frameworks (MOFs) are normally thought of as insulating mateMOF_Stavila.jpgrials, however, with judicious choice of metal ion, linker and guest molecules, the MOFs can be rendered electronically conductive, so that appreciable amounts of charge can occur. The phenomenon is crucial to the implementation of MOFs in optoelectronic devices and sensors. Through various collaborations, we made contributions to the tool-box of techniques necessary to integrate MOF crystals and thin films with functional devices. 

Single-Site Catalysis

Our approach to the design of environmentally friendly and highly active single-site catalysts  is based on principles of solid-state chemistry, biocatalysis, and computational chemistry.singlesite_cat_stavila.jpg This enables rational design of novel open framework catalysts (such as MOFs and COFs) with the ability to independently control the concentrations of Lewis and Brønsted acid sites, as well as the pore size for size-selective catalysis. Single-atom catalytic sites within the open framework can stabilize reactive intermediates and prevent side reactions and deactivation. In this way we have succeeded to design a range of multifunctional catalysts, such as highly selective catalysts for C-O bond hydrogenolysis. Such catalysts could enable efficient processes for transformation of biomass into fuels and value-added products.

Ion transport in solid electrolytes

Ion-transport-in-solid-electrolytes.PNGThe majority of known solids are poor ionic conductors due to high activation energies and the lack of vacant sites for ion migration. Therefore, for a long time the ionic conductivity of solids has been insufficient to supplant liquid electrolytes in battery applications. Very recently, however, a number solids with ionic conductivities comparable to that of liquids have been discovered. The discovery of these fast ion conductors has advanced the prospects for realizing solid-state batteries with improved safety, voltage and energy density. In collaboration with Dr. Terry Udovic at NIST and Dr. Brandon Wood at LLNL, we have developed a suite of solid-state electrolytes based on polyboron clusters which display superionic conductivity, and elucidated the key structural, chemical, and dynamical factors that govern superionic ion transport in this class of materials.

 

Recent Journal Covers

Chem-Review-cover.jpgadvam_cover.jpg

calaysis-cover.jpgpccp-cover.png

Synergistic Activities

  • Boards of review for granting agencies: DOE EERE, ARPA-E, NSF, CRDF, INTAS
  • Journals editorial board member: Frontiers in Energy Storage, Materials
  • Symposium organizer: Organized Symposia at ACS and MRS meetings
  • Sandia-CA X-Ray laboratory coordinator: management of the X-ray diffraction facility and training users on single crystal, powder, thin film, and Small Angle X-ray Scattering (SAXS) instruments.

 

Links:

Transportation Energy research at Sandia National Laboratories 

Hydrogen and Fuel Cell Program at Sandia National Laboratories 

Hydrogen Storage research at Sandia National Laboratories 

Sandia’s Nanoelectronics and Nanophotonics Group

Hydrogen Materials Advanced Research Consortium