Nanocomposites IV: Nanoscience for Renewable Energy: NanoScience Part I
Sponsored by: TMS Structural Materials Division, TMS: Composite Materials Committee
Program Organizers: Changsoo Kim, University of Wisconsin-Milwaukee; Simona Murph, Savannah River National Laboratories; Muralidharan Paramsothy, NanoWorld Innovations (NWI); Meisha Shofner, Georgia Institute of Technology

Monday 8:30 AM
February 27, 2017
Room: Pacific 25
Location: Marriott Marquis Hotel

Session Chair: Simona Murph, Savannah River National Laboratory (SRNL); Muralidharan Paramsothy, NanoWorld Innovations (NWI)

8:30 AM  Keynote
Multifunctional Materials for Renewable Energy Technologies: Federico Rosei1; 1INRS
    The bottom–up approach is considered a potential alternative for low cost manufacturing of nanostructured materials. It is based on the concept of self–assembly of nanostructures on a substrate, and is emerging as an alternative paradigm for traditional top down fabrication used in the semiconductor industry. We demonstrate various strategies to control nanostructure assembly (both organic and inorganic) at the nanoscale. We study, in particular, multifunctional materials, namely materials that exhibit more than one functionality, and structure/property relationships in such systems. In particular, we devised new strategies for synthesizing multifunctional nanoscale materials for electronics and photovoltaics [1-4]. References: [1] R. Nechache et al., Appl. Phys. Lett. 98, 202902 (2011); [2] T. Dembele et al., J. Power Sources 233, 93 (2013); [3] S. Li et al., Chem. Comm. 49, 5856 (2013); [4] R. Nechache et al., Nature Photonics 9, 61 (2015).

9:10 AM  Invited
Ceramic Composites in Diverse Applications Ranging from Oxygen Production to Nuclear Waste Immobilization: Kyle Brinkman1; 1Clemson University
    The emergent properties arising from the interactions of phases including interfacial contributions (including surfaces) and phase evolution at the mesoscale present new opportunities, as well as challenges, for materials performance and functionality. Mixed ionic-electronic conductors are widely used in devices for energy conversion and storage. Grain boundaries and surfaces in these materials have nanoscale spatial dimensions, which can generate substantial resistance to ionic transport. In bulk materials composites may be used to enhance the grain boundary ionic conductivity, while surface coatings are used to target enhanced kinetics. Implications for tailored design of ceramic composites in diverse applications such as high-level nuclear waste immobilization, solid-state Li-ion batteries and solid oxide fuel cells will be discussed.

9:50 AM Break

10:10 AM  Invited
Conditions for Effective Nanocrystal Shape Control in Colloidal SILAR Reactions: Andrew Greytak1; 1University of South Carolina
    Colloidal selective ionic layer adhesion and reaction (colloidal SILAR) is designed to control surface growth in colloidal nanocrystals using a series of self-limiting surface reactions that each supply one of the complementary ions. Though the method was initially described over a decade ago, only recently have the mechanistic assumptions in colloidal SILAR been directly tested. In particular, shape control via SILAR can only be achieved if the complementary precursors are efficiently converted to surface-bound forms in each half-cycle. Our group has investigated colloidal SILAR in the CdSe/CdS core/shell quantum dot system. ICP-MS measurements show that the choice of solvent can strongly influence precursor conversion. Commonly used primary amine solvents suppress Cd oleate conversion. We find that a tertiary amine solvent is effective in increasing precursor conversion and suppressing nucleation of side products. Under optimized conditions, good control of size and shape can be achieved with saturating precursor doses.

10:50 AM  Invited
Hydrogen Storage, Ionic Conduction, and Photophysical Properties of Fullerene Based Materials: Joseph Teprovich1; Patrick Ward1; Aaron Washington1; Hector Colon-Mercado1; Ragaiy Zidan1; 1Savannah River National Laboratory
    Our investigation of the interaction of metal hydrides and complex metal hydrides with carbon nanostructures (C60, CNT’s, etc.) has demonstrated that these composites reversibly interact with hydrogen. Through a series of spectroscopic analysis of these materials, the active hydrogen storage material resembles a metal-doped hydrogenated fullerene. Owing to our ability to judiciously control the metal doping and hydrogen content of these materials, we can fine-tune the properties of the materials for new applications. This led to the remarkable enhancement in lithium ion conduction in LiBH4-C60 nanocomposites observed at room temperature. Experimental and theoretical work suggested a nanoionic mechanism is responsible for the enhanced ionic conduction due to the destabilization/breaking of the Li+/BH4- ion pair by C60. The photophysical properties of these carbon nanocomposites have also been investigated. The hydrogen content of these materials can be used fine-tune the emissive properties of the material with potential applications in luminescence down-shifting devices.