From a materials design perspective, phosphates offer nearly limitless possibilities for various applications, chelating agents, synthetic replacements for bone and teeth, phosphors, detergents, and fertilisers. As a consequence of its thermal and chemical properties, Barium Hydrogen Phosphate (BaHPO₄) plays an important role in catalytic chemistry, industrial paint manufacturing, and ink-related charge direction. Because hydrogen and hydrogen bonds significantly affect these properties, studying proton mechanisms such as proton diffusive motions and jumps is critical to developing a comprehensive understanding pf the compound, allowing further determination of potential applications. Here, we utilise incoherent Quasi-Elastic Neutron Scattering (QENS). QENS is a useful technique to determine diffusive motions in the 10^-12 to 10^-9 second time range at length scales from 3Å to 60Å, which apply to hydrogen ion diffusion and hydrogenous species. Protons have a substantial neutron cross section, which subsequently enchances the associated QENS signal, and permits studies for low-proton systems such as BaHPO₄. The QENS investigation was conducted using 7 discrete temperatures ranging from 293 to 572 Kelvin, while subsequent fitting and analysis revealed the diffusion coefficient as a function of temperature. Obtained results for BaHPO₄ were compared to Monetite (CaHPO₄). In addition to QENS, Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM) provided support by giving insight to the surface topography of the sample. Structural and topographic results were compared with similar studies of other relevant phosphates.

Localization, mapping, and navigation are common tasks in robotics but, in the case of robots with limited sensors and processing power, these tasks can be difficult to reliably achieve. Particularly in the field of personal robotics, robots are often built with limited capabilities in the interest of making them more affordable. This increases the likelihood that such robots will fail at various components of its navigation tasks. To address this, we propose developing a robot that can determine when it has failed, intelligently ask humans for help in such scenarios, and learn from that help to better address these scenarios in the future. To achieve this goal, we will develop a web-based teleoperation interface for Kuri, a relatively simple personal robot. Challenges involved in this goal are the reduction of video latency between Kuri and its interface as well as how to design the teleoperation interface to make it easy for humans to use. Such an interface will make it possible for humans to directly interact with the Kuri and aid it in difficult situations. This teleoperation interface will be one of multiple strategies that Kuri will use to ask humans for help. These strategies include explicitly asking a human to tell Kuri where it is through a text or even speech interface or, similarly, answering other queries that help Kuri in understanding its environment. We will then run experiments to determine how willing humans are to provide different types of help to Kuri, how useful each type of help is to the robot, and in what scenarios the robot should utilize each type of help. This project will help us understand to what extent human aid can make navigation easier for robots and, ultimately, this will further bridge the gap between humans and robots in personal environments.

As the world's climate situation becomes more dire, the need for a clean, renewable energy source becomes more pronounced. Proton conductor fuel cells (PCFCs) use the chemical energy of hydrogen fuel efficiently and cleanly to produce electricity with zero-emission. A proton conductor electrolyte is the heart of the fuel cell operation. Alkaline phosphates such as SrHPO₄ are an attractive class of compounds for potential electrolyte materials in proton conducting fuel cells; understanding the crystal structure as function of temperature, the way crystal defects affect structure, the proton conductivity, and resultant properties is of great importance to the advancement of both science and industry. To this end, we are interested in making progress in the science of phosphates as potential proton conductors by studying the structure of SrHPO₄ and other aliovalent (Ca, Ba) phosphate materials by neutron powder diffraction (NPD). Studying the phosphate family allows us to characterize the correlation between the aliovalent alkaline-earth oxide local structures and the measured dynamics properties. An advanced comprehension study of the change in structure of SrHPO₄ as a function of temperature will provide clues to the relationship between structure and the dynamics of proton conduction. In an effort to better understand the structural properties of SrHPO₄ as a function of temperature, NPD data was collected in temperatures ranging from 6K to 300K. X-ray Diffraction(XRD) was performed at 150K and 300K. Surface topography was studied via Scanning Electron Microscopy(SEM) and Atomic Force Microscopy (AFM), collected at Oak Ridge National Laboratory (ORNL). The NPD data was analyzed using the Rietveld Method in conjunction with the FullProf software tool, and we will compare the results with those of CaHPO₄ and BaHPO₄ in order to better understand the relationship between the crystal structure and the proton conduction dynamics of these materials.

We probe the crystal structure and the proton conductivity of magnesium hydrogen phosphate trihydrate MgHPO₄·3H₂O, also known as newberyite. Newberyite is used as an ingredient in pigments, plastics, and anticorrosive paints, and as an alkaline phosphate it has potential for use in proton conduction. The structural transition and the proton diffusive motion as a function of temperature from 20K to 383K have been studied using X-ray crystallography, quasi-elastic neutron scattering (QENS) spectroscopy and atomic force microscopy (AFM), collected from the National Institute of Standards and Technology (NIST) and the Center for Nanophase Materials Sciences (CNMS) at Oak Ridge National Laboratory (ORNL). We confirm that newberyite undergoes a crystalline-to-amorphous dehydration phase transition at low temperatures, which is unusual in other phosphate materials. We compare our analysis with previous crystallographic surveys.

SrHPO₄ is of interest as a candidate material for use in proton-exchange membranes, as a startup material for ceramic fuel-cells, and as a catalyst, but until now its proton mobility had not been studied by quasi-elastic neutron scattering (QENS). QENS analysis of a material provides an understanding of its usefulness for these applications. It displays the behavior of proton diffusion processes in a sample, and the stability of such processes at a wide range of temperatures is crucial to the success of a candidate material. A QENS experiment was performed at the National Institute of Standards and Technology (NIST) on SrHPO₄ powder from 20K to 523K using a Disk Chopper Spectrometer (DCS). Data analysis was then conducted to gain insight into the properties of the sample at each of these temperatures. The data was modeled with background, delta, and Lorentzian functions, as parameters of these models constrain the physical behavior of protons in SrHPO₄. These results were compared with a QENS analysis of Monetite (CaHPO₄) to provide further context to our findings.