A Novel Technique for the Production of Robust Actinide Targets

Khachatur Manukyan University of Notre Dame

1 GOALS & OBJECTIVES & MILESTONES

The GOAL of this project is to develop new approaches for the preparation of actinide targets that are isotopically pure, cost-efficient, reliable, robust, and highly uniform with controlled thicknesses.

The core of the program relies on the use of rapid solution combustion synthesis (SCS) processes between actinide metal nitrates with different organic compounds for the preparation of thin films as targets for nuclear science measurements.

OBJECTIVES: (1) Investigate chemical reactions between oxidizers and organic compounds (2) Investigate thin films deposition (3) Investigate electrospray techniques with actinide-oxide clusters (4) Create actinide targets by electrospray deposition (5) Characterize and test targets (6) Modernize targetry and target preparation

MILESTONES: • Determine the dynamics and kinetics data of SCS reaction for actinides September 30, 2019 • Apply the method to produce uranium targets and their characteristics September 30, 2020 • Extend the procedure to other actinide nuclei such as Pu and Am. September 30, 2021

2 Team

A. Aprahamian, PI P.C. Burns K. Manukyan Graduate Students

S. Dede A.Majumdar Jordan Roach Bryce Frentz Sabrina Strauss Physics Physics Chemistry Physics Seismic Imaging Analyst Texas A&M Notre Dame Notre Dame Notre Dame Houston, TX Undergraduate students

Jacob Galden Nathaniel Hiott Chem. Eng. Physics

3 Articles

Published: 1. I.P. Borovinskaya, K.V. Manukyan, A.S. Mukasyan, SHS Ceramics: History and Recent Advances, Ceramics in Modern Technologies, 1, 3-19 (2019). 2. A.S. Mukasyan, S. Roslyakov, J.M. Pauls, L.C. Gallington, T. Orlova, X. Liu, M. Dobrowolska, J.K. Furdyna, K.V. Manukyan, Nanoscale Metastable ε Fe3N Ferromagnetic Materials by Self-Sustained Reactions, Inorg. Chem., 58, 5583−5592 (2019). 3. S.L. Kharatyan, H.A. Chatilyan, K.V. Manukyan, Kinetics and Mechanism of Nickel Oxide Reduction by Methane, J. Phys. Chem. C, 123, 21513-21521 (2019) 4. E. Aleksanyan, A. Aprahamian, A.S. Mukasyan, V. Harutyunyan, and K.V. Manukyan, Mechanisms of mechanochemical synthesis of cesium lead halides:

pathways toward stabilization of α-CsPbI3, J. Mater. Sci. 55, pages 8665–8678 (2020). 5. P. Sapkota, A. Aprahamian, K.Y. Chan, B. Frentz, K.T. Macon, S. Ptasinska, D. Robertson, K.V. Manukyan, Irradiation-induced reactions at the

CeO2/SiO2/Si interface, J. Chem. Phys. 152, 104704 (2020). 6. V.V. Baghramyan, A.A. Sargsyan, N.B. Knyzyan, V.V. Harutyunyan, A.H. Badalyan, N.E. Grigoryan, A. Aprahamian, K.V. Manukyan, Pure and cerium- doped zinc orthosilicate as a pigment for thermoregulating coatings, Ceram. Intern, 46, 4992-4997 (2020). 7. N. Amirkhanyan, S.L. Kharatyan, K.V. Manukyan, A. Aprahamian, Thermodynamics and Kinetics of Solution Combustion Synthesis: Ni(NO3)2 + Fuels Systems, under review at Combustion and Flame, 221, 110-119 (2020).

Submitted: 1. B. Frentz, A. Aprahamian, A.M. Clark, C. Dulal, J.D. Enright, R.J. deBoer, J. Görres, S. L. Henderson, K.B. Howard, R. Kelmar, K. Lee, L. Morales, S. Moylan, Z. Raman, W. Tan, L. E. Weghorn, and M. Wiescher “Lifetime measurements of excited states in 15O”. Physical Review C, 2021 2. S. Strauss, A. Aprahamian, C. Casarella, P.J. Fasano, B. Frentz, K. Manukyan, C. Reingold, M. Smith, W. Tan, S. R. Lesher, C. Hughes, “Measurements of E0 Transitions in 154Gd with ICEBall” Physical Review C, 2021 3. M.K. Zakaryan, S.L. Kharatyan, A. Aprahamian, K.V. Manukyan, Zirconium Silicide Ceramics Prepared by Metal Reduction of Zirconium Tetrafluoride, Combustion and Flame, 2021

In preparation: 1. J.M. Roach, K.V. Manukyan, A. Majumdar, S. Dede, J. Galden, P.C. Burns and A Aprahamian, Solution Combustion Synthesis of Uranium Oxides Nanomaterials and Thin Films, will be submitted to Inorganic Chemistry. 2. A. Majumdar, K.V. Manukyan, J.M. Roach, S. Dede, D. Robertson, P.C. Burns and A Aprahamian, Solution combustion synthesis of thin uranium oxide films for nuclear target applications, will be submitted to ACS Applied Materials & Interfaces. 3. S. Dede, J. Roach, A. Majumdar, K.V. Manukyan, P.C. Burns and A. Aprahamian, Actinide Target Materials for Nuclear Physics Measurements, A Review article will be submitted to Nuclear Instruments and Methods Phys. Res. Sect. A 4 Research results

5 Mechanism of the Solution Combustion Synthesis (SCS) Differential scanning calorimetry (DSC) and Thermogravimetric Analysis (TGA)

UO2(NO3)2 + C2H5NO2 (glycine) + H2O system

Jordan Roach

Crystal structure of uranyl-glycine (U-Gly) complex HNO3 + C2H5NO2 system DSC/TGA of U-Gly-1 complex

6+ 2+ + • [U(H2O)n] → [UO2(H2O)4] + 4H + (n−4)H2O • U-Gly complex formation

• 4HNO3 → 2H2O + 4NO2 + O2

• Oxidation of C2H5NO2 by NO2 and O2 • Exothermic decomposition of U-Gly complex 6 Kinetics of Combustion Processes: Kissinger analysis

Jordan Roach 1 ln = + ln 𝐵𝐵 𝐸𝐸 𝐴𝐴𝑅𝑅 2 − 𝑇𝑇𝑚𝑚 𝑅𝑅 𝑇𝑇𝑚𝑚 𝐸𝐸 A - pre-exponential factor B - heating rate (K/s) R - gas constant (J K−1 mol−1) E = activation energy (kJ/mol) ⋅ ⋅ Tm = max temperature (K)

ANALYTICAL CHEMISTRY VOL. 29, 1957, 1703

The oxidation of glycine is responsible for the ignition of SCS 7 Thermal Analysis of Combustible Solutions

UO2(NO3)2 + C3H8O2 (acetylacetone) solution in 2-methoxyethanol

DSC-TGA results X-ray diffraction (XRD) pattern

400oC

20 min 10 min

5 min

Endotherm peak - evaporation of 2-methoxyethanol SCS and short annealing allows

Exothermic peak – combustion of UO2(NO3)2 + C3H8O2 preparing crystalline UO2 powder8 UO2 target preparation and characterization X-ray fluorescence elemental distribution maps

Ashabari Majumdar

Spin-coating-assisted combustion synthesis

(Α)α-particle emission spectra (B-E) U atoms per cm2

Annealing at 400oC for 20 minutes during each cycle

• Simple setup • 35% material collection efficacy • Ability to reuse the waste material • Deposition on different backings • High control over the deposited material quantity 9 Electron Microscopy

Plane view (A-D) and cross-sectional (E-H) SEM images for samples with different UO2 layer thicknesses, HAADF TEM (I), and high-resolution TEM images (J and K) as well as electron 10 diffraction pattern (L) of film with Al substrate. Target Stability: Ion irradiation tests

5U Sta. Ana accelerator

• UO2 deposited on Al • Ar2+ beam (1.7 MeV) • Up to 1·1017 ion/cm2

11 Stoichiometry of UO2+x Targets: X-ray photoelectron spectroscopy

Non-irradiated 1·1016 ion/cm2 1·1017 ion/cm2 Oxygen coefficient (k0) K0=2+x U 5f = = 5.366 . U 4f −7 173 𝐼𝐼1 𝑘𝑘0 =7⁄20.0383 + 0.1149 Core level

𝐼𝐼2 =− 𝑘𝑘0

𝐼𝐼3 2𝐼𝐼1 − 𝐼𝐼2 ( ) = 0.0383 4+ 𝐼𝐼3 𝑣𝑣1 𝑈𝑈 2( ) ( ) = 0.0383 5+ 𝐼𝐼2 − 𝐼𝐼1 𝑣𝑣2 𝑈𝑈 0.0383

Valence band band Valence ( ) = 0.0383 6+ − 𝐼𝐼2 𝑣𝑣3 𝑈𝑈 Table 1 Oxygen coefficient (ko) and surface ionic composition of UO2+x films

Irradiation I1 ko=2+x I2 I3 ν, % fluence, ion/cm2 U4+ U5+ U6+ 0 0.0324 2.039 0.037 0.028 73 23 4 Inorg. Chem. 2016, 55 (16), 8059–8070 16 1·10 0.0317 2.045 0.037 0.027 70 25 5 12 1·1017 0.0345 2.021 0.038 0.032 82 16 2

Target preparation and characterization Electro-spraying of reactive solutions • Simple setup • 100% material collection efficacy • Deposition on different backings S. Dede Physics Texas A&M

Aluminum backing Carbon backing

13 Exploring the electro-spraying parameters

320 µg/cm2

35 µg/cm2

14 The effect of heat treatment temperature Bright Field TEM images 350oC 450oC 550oC

High resolutionTEM images 350oC 450oC 550oC Target preparation and testing

• Over 200 depleted UO2 targets on Al and C backings were prepared • The targets were fully characterized and tested for irradiation stability

• Over 25 targets have been shipped to LANL S. Dede A.Majumdar • Four members of our group traveled to NANL • Targets were tested in neutron capture and fission fragment measurements at LANL • The result of these tests are being analyzed W. Tan K. Manukyan

shipped to LANL

Target test using DANCE at LANL Next steps

• Finish analysis of target tests • Investigate target deposition methods using actinide-oxide clusters • Develop deposition method for target with higher activities • Continue dissimilation of results, facilitate the modernization of targetry and target preparation

17 Conclusions and Acknowledgments

• The students are trained on a large variety of chemistry, materials science and nuclear physics techniques. • Information on the dynamics and kinetics of SCS for depleted uranium oxides have been obtained. • Simple and Efficient SCS-based methods of thin UO2 target depositions were developed. • A large number of targets have been prepared, fully characterized, and tested.

Special thanks to Aaron Couture, Christopher Prokop, Shea Mosby, Dana Duke , Michael Mocko and Morgan White for their assistance in the target tests at LANL.

18 Thank you !!! Actinide-oxide clusters as source for target materials

228˚C 410˚C 500˚C 1000˚C 25˚C

Polyhedral representation of a U32R uranyl peroxide cluster

DSC-TGA data for the thermal Temperature – time profile for the combustion reaction decomposition of U32R clusters in air of U32R – Hexamethylenetetramine mixture