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Title: Room temperature synthesis of UO 2+x nanocrystals and thin films via hydrolysis of uranium( iv ) complexes
Methods for the straightforward, room temperature synthesis of UO 2+ x nanoparticles and thin films using solution processable, molecular uranium( iv ) compounds is described. Ultra-small uranium dioxide nanoparticles are synthesized from the hydrolysis of either U(ditox) 4 (ditox = − OCH t Bu 2 ) (1) or U(CH 2 SiMe 2 NSiMe 3 )[N(SiMe 3 ) 2 ] 2 (2) via addition of water to stirring solutions of the compounds in non-polar solvents to give UO 2 -1 and UO 2 -2, respectively. The structural characteristics of the uranium dioxide nanoparticles were characterized using powder X-ray diffraction (pXRD), high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy. The pXRD results affirm the cubic fluorite structure expected for UO 2 nanoparticles. The nanocrystallinity of UO 2 -1 and UO 2 -2 were substantiated by bright-field HRTEM images and fast Fourier transform (FFT) patterns. The HRTEM analysis also shows the nanoparticles fall within the ultra-small regime possessing sizes of ∼3 nm with uniform distribution. Additionally, we demonstrate the versatility of 1 as a uranium dioxide precursor, showing that it can be readily sublimed onto glass or silicon substrates and subsequently hydrolyzed to give UO 2+ x thin films.  more » « less
Award ID(s):
1827875
NSF-PAR ID:
10309161
Author(s) / Creator(s):
 ;  ;  ;  ;  ; ;  ;  ;  
Date Published:
Journal Name:
Inorganic Chemistry Frontiers
ISSN:
2052-1553
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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