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Research Interest
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Photoelectrochemical hydrogen generation;
Hydrogen storage using CNT and titania composites;
Materials for high temperature nuclear reactors;
Nanotube and nanowire materials and devices
Boron nitride nanotubes;
Nanoporous materials;
Second generation nuclear waste-package design;
Corrosion of materials used in YMP;
Radiation detectors;
Arsenic removal;
Recycling Spent Nuclear Fuel; and
Biofuels: coffee grounds and nonfood materials
Currently Funded Research at UNR
Funded Research at the University of Nevada, Reno - Total Around 23 Million Dollars
Advanced Research and Development in Materials Reliability $2,681,400 (expected date 10/01/08 – 09/30/11)
Photo-Electrochemical Generation of Hydrogen Using Semiconductor Titania Nanotubes, U.S. Dept. of Energy, $3,047,250 (9/1/06-8/31/09)
Nuclear Materials, DOE-Advanced Fuels Cycle Initiative, $990,000 (5/27/06-01/31/09)
Radioactive Contaminants in Water, DOE-NNSA, $2,715,000 (10/1/05-9/30/08)
Fundamentals of Surface Reactions, DOE-EPSCoR, $482,445 (8/1/06-7/31/09)
Yucca Mountain Corrosion-Task 14, DOE-ORD, $1,396,759 (6/1/04-9/30/08)
Mass Balance of Mercury, Center for Advanced Separations, $88,897 (7/26/06-9/30/08)
Nanotube and Nanowire R&D, DOE-Technology Development, $966,475 (06/30/05- 09/30/08)
Environmental Effects on Corrosion Properties of Alloy 22, DOE-YMP, ($3,571,974, 06/01/04-9/30/08)
Materials Evaluation, Degradation, and Modeling, Dept. of Energy Basic Science, $744,000 (09/30/06-
12/31/08)Previously Funded Research at UNR
Nanoelectrode Arrays for Radiation Sensing, $400,000
Arsenic Removal Research, Eagle-Picher and ARI, $173,492
Pressurized Oxidative Process for Recovery of Energy from Biomass, $620,000, Dept. of Energy – Energy Efficient
Environmental Corrosion, Dept. of Energy – Civilian Radioactive Waste, $845,000
Nuclear Waste Repository Materials, DOE-Basic Sciences Division, $966,000
Nanomaterials and Devices, NSF-EPSCoR, $116,110
Hydrometallurgical Processing of Chalcopyrite, DOE - Center for Advanced Separation Technology, $165,000 (Co-PI)
New Reagent for Dolomite Processing, DOE - Center for Advanced Separation Technology, $165,943 (Co- PI)
NanoBlox Nano Diamond Effects on Electroplating of Copper for Semiconductor Interconnects, $50,000
Arsenic Filtration, Eagle-Picher, $46,000, ARI $46,000
CFT Professorship $24,000
Acquisition of Transmission Electron Microscope for Materials Research, $800,000, NSF (2003-2005) and UNR match $600,000
Hydrometallurgical Processing of Chalcopyrite, DOE-CAST, $160,982
Nanomaterials and Devices, NSF-EPSCoR, $115,168
Advanced Fuels Processing, $45,000, Clean Fuels Technology
Arsenic Filtration, Novation and ARI, $32,000
Solar Cells, Altair Nanomaterials and ARI, $70,000
Nanotechnology Research, First Nano and ARI, $105,000
Nanomaterials & Devices, NSF-EPSCoR, $160,000
Centrifugal Gravo-Magnetic Separation of Radionuclides from NTS Soil, $111,526
Innovative Technologies for Environmental Remediation: Technology Research, Inc., $70,000
Acid Rock Passivation, State of South Dakota and Hecla, $17,500
Research and Development of Emulsified Fuels, Clean Fuels Technology, $240,000 and Applied Research Initiative (ARI), $50,000
Lab-Scale Testing of Passivation Technology for Newton Copper Mine, CAL-FED, $60,000
Passivation Technology for Gilt-Edge Operation, MSE Inc., $13,000
Industrial Consortium, $20,000
Centrifugal Gravo-Magnetic Separation, DOE, $111,526
Acid Rock Passivation, CalFed-EPA, $60,000
Keratin Protein for Environmental Application, Maxim, $50,000
ndustrial Consortium, $50,000
Emulsified Fuels, Clean Fuel Technologies, $110,000
Innovative Technologies: Technologies Research, Inc., $120,000 and ARI: $50,000
Centrifugal Gravo-Magnetic Separation (CGMS) Technology for Removal of Radionuclides from NTS Soil: DOE, $111,526
Remediation of Radium Contaminated Soil: EPA, $172,727
Thermo-Mechanical Properties of Nuclear Weapon Materials, Co-PI: DOE, $150,000
Biotechnological Processing: Geobiotics and ARI, $125,000
Acid Rock Passivation: Hecla and SD-DNER, $17,500
Cyanide Destruction: Hecla and ENVIRITE, $20,000
Precious Metal Recovery, Industrial Consortium, $30,000
Mixed Waste Remediation by Supercritical CO2, DOE, $44,760
Remediation of Radium Contaminated Soil, EPA, $172,727
Barrier for Tritium, Radon and Other Isotopes, DOE $60,000
Bioxidation Pilot Plant, Geobiotics and ARI, $110,000
Novel Process for De-inking Office Waste Papers, Framatome Technologies and ARI, $110,000
Precious Metal Extraction, Industrial Consortium and ARI, $110,000
Thermal and Mechanical Properties of Nuclear Weapon Materials, DOE, $780,000
Remediation of Radium Contaminated Soil, EPA, $172,727
Johnston Atoll Remediation, OHM, $20,000
Mixed Waste Remediation, DOE, $44,760
Removal of Mercury, Newmont, $28,000
Arsenic Removal, Tech Metals and ARI $110,000
Biooxidation, Geobiotics and ARI, $101,628
Zinc Sulfate Process, Colonial, $50,000
Selective Removal of Mercury, USBM, $136,000
Removal of Oxyanions of Arsenic and Selenium, USBM, $123,000
Industrial Support, $41,000
Mixed Waste Remediation, DOE, $44,760
Selective Removal of Mercury, USBM, $136,000
Removal of Oxyanions of Arsenic and Selenium, $123,000
Biooxidation, Geobiotics, $51,628
Misc. Industrial Support, $50,000
Mine Waste Remediation, EPA-EPSCoR, $201,000
Characterization and Physical Separation of Radionuclides from NTS, DOE, $201,174
Phosphate Flotation: FIPR, $69,300
Mine Waste Remediation and Treatment, EPA-EPSCoR, $201,000
Mitigation of Acid Mine Drainage by Agglomeration and Encapsulation of Acid Mine Tailings, USBM,
$41,000Removal of Oxyanions of Selenium and Arsenic, USBM, $123,000
Selective Removal of Mercury from Gold Cyanide Circuits, USBM, $136,000
Characterization and Physical Separation of Radionuclides From NTS Contaminated Soils, DOE, $61,436
NTS Plutonium Stabilization, Martin Marietta, $25,000
Advanced Concepts in Mineral Processing, Industrial Consortium, $54,000
Characterization and Removal of Plutonium from Johnston Atol Coral Sand, DoD, $88,000
Heavy Metals Contaminated Soil, Soil Washing Operations, DOE, $1,262,981
Mitigation of Acid Mine Drainage by an Agglomeration and Encapsulation of Acid Mine Tailings, USBM,
$41,765Removal of Oxyanions of Selenium and Arsenic, USBM, $61,000
Selective Separation of Coal from Ash and Pyrite With a Novel Mycobacterium phlei, DOE, $139,130
Advanced Concepts in Mineral Processing, Industrial Consortium, $50,475
Plutonium Contaminated Soils, DOE, $150,000
Mitigation of Acid Mine Drainage by an Agglomeration-Encapsulation Process, USBM, $51,577
Advance Concepts in Mineral Processing, Industrial Consortium, $50,000
Selective Removal of Coal From Ash and Pyrite, DOE, $139,130
Soil Decontamination Research, DOE, $50,000
Mitigation of Acid Mine Drainage by Agglomeration-Encapsulation Process, USBM, $51,577
Flocculation of Kerogen with Hydrophobic Mycobacterium phlei, DOE, $25,000
Mineral Processing Conference, NSF, $12,000
Recovery of Tar Sands by Solvent Extraction, DOE, $106,535
Recovery of Tar Sands by Solvent Extraction Process, DOE, $106,539
Pressure Cycle Comminution of Eastern Oil Shale, DOE,
A More in Depth Research Overview
Jump to:
Hydrogen Generation
Photo-electrochemical hydrogen generation using band-gap modified nanotubular titanium oxide in solar light
K.S. Raja, M. Misra, V.K. Mahajan, T. Gandhi, P. Pillai, S.K. Mohapatra
Anodization of Ti in acidified fluoride solution results in an ordered nanotubular titanium oxide surface. In this study, vertically oriented arrays of TiO2 nanotubes were prepared by incorporating nitrate and phosphate species during the anodization process. These nanotubes were annealed at 650°C in a carbonaceous atmosphere using a chemical vapor deposition (CVD) furnace for a brief period. The carbon-modified nanotubular TiO2 produced a photo-current density of more than 2.75mAcm−2 at 0.2VAg/AgCl under solar light illumination. This photo-current density corresponds to a hydrogen evolution rate of about 11 l h−1 using a photo-anode of 1m2 area. The enhanced hydrogen evolution behavior of carbon-modified nanotubular TiO2 is highly reproducible and sustainable for long duration. Annealed (at 350°C in nitrogen atmosphere) TiO2 nanotubes showed improved photo-activity as compared to the as-anodized or thermally oxidized TiO2 photo-anodes.
Full Text
Determination of photo conversion efficiency of nanotubular titanium oxide photo-electrochemical cell for solar hydrogen generation
K.S. Raja, V.K. Mahajan, M. Misra
Anodized and annealed titanium oxide nanotubes showenhanced photo activity and can be used as photo anodes forwater electrolysis in hydrogen generation. Application of an external potential to the photo anode is required for enhancement of the photocurrent. This additional electrical energy input complicates the photo conversion efficiency calculation. In this investigation, the photo-electrochemical behavior of anodized titanium oxide nanotubular arrays have been characterized in various electrolytes. Increase in the applied potential increased the photocurrent under illumination with visible light. A simple experimental method for calculating the photo conversion efficiency has been proposed. According to this method, the potential difference between the photo anode and cathode is measured with and without light illumination. The product of the photocurrent and the increase in potential due to light irradiation is considered as the net power output. The photocurrent and the conversion efficiency increased with increase in the pH of the electrolyte. TiO2 nanotubular arrays annealed at 350°C for 6 h in nitrogen atmosphere showed a maximum photo conversion efficiency of ∼4% in 1M KOH electrolyte and ∼3% in 3.5 wt.% sodium chloride solution. The results indicate that nanotubular TiO2 can be potentially used for the photo electrolysis of seawater to generate hydrogen.Full Text
Hydrogen Storage
Electrochemical storage of hydrogen in nanotubular TiO2 arrays
P. Pillai, K.S. Raja, M. Misra
Vertically oriented nanotubular TiO2 arrays were formed by a simple anodization process. Hydrogen storage studies were carried out on the TiO2 nanotubular arrays having different diameters by charging and discharging hydrogen with potentiostatic/galvanostatic control. The hydrogen storage capacities of the nanotubes were only marginally affected by the tube diameter. Concentration of oxygen vacancies as defects influenced the hydrogen storage of the nanotubes. Annealing of the TiO2 nanotubes in argon atmosphere increased the defect density and decreased the hydrogen discharge during initial charge-discharge cycles. Hydrogen storage studies through electrochemical route did not show significant storage capacity of TiO2 nanotubes. Diffusion of hydrogen as protons and interference of the double layer capacitance of nanotubes could be attributed to the lower hydrogen storage capacity.Full Text
Sensors
Templated growth of cadmium zinc telluride (CZT) nanowires using pulsed-potentials in hot non-aqueous solution
T. Gandhi, K.S. Raja, M. Misra
A single step non-aqueous electrodeposition of cadmium zinc telluride (CZT) nanowires on nanoporous TiO2 substrate was investigated under pulsed-potential conditions. Propylene carbonatewas used as the non-aqueous medium. Cyclic voltammogram studies were carried out to understand the growth mechanism of CZT. EDAX and XRD measurements indicated formation of a compound semiconductor with a stoichiometry of Cd1−xZnxTe, where x varied between 0.04 and 0.2. Variation of the pulsed-cathodic potentials could modulate the composition of the CZT. More negative cathodic potentials resulted in increased Zn content. The nanowires showed an electronic band gap of about 1.6 eV. Mott-Schottky analyses indicated p-type semiconductor properties of both as-deposited and annealed CZT materials. Increase in Zn content increased the charge carrier density. Annealing of the deposits resulted in lower charge carrier densities, in the order of 1015 cm-3.
Full Text
Electrodeposition of Al-Sb nanowire arrays for radiation detection
S.K. Mohapatra, T. Gandhi, M. Misra and K.S. Raja
Full Text
CZT and AlSb Nanowire Arrays for Radiation Sensing
T. Gandhi, K.S. Raja, M. Misra, S.K. Mohapatra
PPT File
Nanotubes and Nanowires
Formation of self-ordered nano-tubular structure of anodic oxide layer on titanium
K.S. Raja, M. Misra, K. Paramguru
Room temperature anodization of titanium foil specimens was carried out in 0.5 M phosphoric acid solution with addition of various halide ions. Addition of 0.138M HF or NaF resulted in self-ordered nano-tubular oxide structure. Addition of bromide and chloride ions initiated only pitting and nano-pores were not observed during anodization. Acidified fluoride solution is found to be necessary to obtain ordered nano-structure as neutral fluoride solution did not form nano-pores. Instability of the oxide layer during anodization and formation of the self-ordered structure can be explained by the perturbation theory. Separation of individual nano-tubes of titanium oxide layer from the inter-connected nano-pores could be attributed to the possible repulsion forces of the cation vacancies.
Deposition of calcium phosphate coating on nanotubular anodized titanium
K.S. Raja, M. Misra, K. Paramguru
Nanotubular anodic oxide layer was grown on titanium surface by room temperature anodization in 0.5 M H3PO4+0.138 M fluoride solution. The inner surface of the nanotubular oxide walls contained adsorbed anions from the solution that were predominantly phosphate. Hydroxy apatite was electrodeposited on the anodized surface of Ti. Adsorbed phosphate ions facilitated nucleation of nanophase calcium phosphate material inside the nanotubular structure that resulted in vertical growth of apatite crystals. Bond strength of the calcium phosphate coating was found to be good, and cohesive mode of failure of the coating was observed after tensile testing. Full Text
Nuclear Materials
Critical Issues on Selection of Candidate Materials for Out-of-Core Structural Applications in Generation IV Nuclear Reactors
M. Misra, K. S. Raja, Y. Ashida, S. Badwe
The structural materials of Generation IV nuclear reactors will be exposed to severe environmental conditions in combination with increased radiation damage. The critical issues on the selection of candidate materials, such as phase stability and creep-fatigue interaction at elevated temperature; irradiation induced microstructural alterations and mechanical properties changes; and environmental degradation in liquid sodium and lead-bismuth eutectic have been discussed. The need for fracture mechanistic approach to estimate the creep-fatigue crack initiation and crack growth rates for estimating the lifetime is highlighted. As surface oxide film formation and growth control the corrosion behavior of structural materials, an improved mechanistic understanding of passivity and its breakdown in liquid metal environments is required for assessing the lifetime. Full Text
Nuclear Repository
A study of corrosion behavior of Ni-22Cr-13Mo-3W alloy under hygroscopic salt deposits on hot surface
Sunil Badwe, K.S. Raja, M. Misra
Alloy 22, a nickel base Ni-22Cr-13Mo-3W alloy has an excellent corrosion resistance in oxidizing and reducing environments. Most of the corrosion studies on Alloy 22 have been conducted using conventional chemical or electrochemical methods. In the present investigation, the specimen was directly heated instead of heating the electrolyte, thereby simulating the nuclear waste package container temperature profile. Corrosion behavior of Alloy 22 and evaporation conditions of water diffusing on the container were evaluated using the newly devised heated electrode corrosion test (HECT) method in simulated acidifiedwater (SAW) and simulated concentratedwater (SCW) environments. In this method, the concentration of the environment varied with test duration. The corrosion rate of Alloy 22 was not affected by the continuous increase in ionic strength of the SAW (pH 3) environment. Passivation kinetics was faster with increase in concentration of the electrolytes. The major difference between the conventional test and HECT was the aging characteristics of the passive film of Alloy 22. The heated electrode corrosion test can be used for evaluating materials for construction of heat transfer equipments such as evaporators.
Radially Configured Waste Package Designs For The Yucca Mountain Repository
P. Kar, G. Danco
Waste packages (WPs) with variable heat loads keep up disposal costs and make the colder packages susceptible to aqueous transport around them during the condensation period of several centuries or thousands of years. Although the condensation on waste packages is described and recognized in the literature, the effect of it on the safety of the containment is not fully understood. Radially configured waste package design, a novel concept for packaging nuclear waste, is presented as a solution for maintaining higher temperatures for low-heat output WPs for sufficient time to delay the effect of liquid water condensate. The radial configuration can package more nuclear waste for a given internal volume than the currently implemented Cartesian configuration. Moreover, radial designs transfer heat more efficiently from the nuclear waste to container surface. Radially configured nuclear waste package designs are described for boiling water reactor (BWR) and pressurized water reactor (PWR) assemblies disposed with different combinations of vitrified high-level waste (HLW) canisters. Thermal analyses of the radial designs confirm the feasibility of the designs demonstrating that no over-heating occurs in contained nuclear waste.
Second Generation Waste Package Design And Operating Concept For Disposal Of High Level Waste At The Yucca Mountain Repository
J.S. Armijo, P. Kar and M. Misra