Improved Neutron Scintillators Based on Nanomaterials

Dennis Friesel, PhD

关键词: ABSORPTION;    DOCUMENTATION;    EFFICIENCY;    FABRICATION;    LIGHT SCATTERING;    LIGHT TRANSMISSION;    NEUTRON DETECTION;    NEUTRONS;    PHOSPHORS;    POLYSTYRENE;    SCINTILLATIONS;    THICKNESS;    TOLUENE Neutron;    Scintillator;    Organic;   

DOI  :  10.2172/948088
RP-ID  :  DOEER84885
PID  :  OSTI ID: 948088
Others  :  TRN: US1000940

美国|英语

来源: SciTech Connect

【 摘 要 】

The development work conducted in this SBIR has so far not supported the premise that using nano-particles in LiFZnS:Ag foils improves their transparency to 420 (or other frequency) light. This conclusion is based solely on the light absorption properties of LiFZnS foils fabricated from nano- and from micro-particles. Furthermore, even for the case of the Gd{sub 2}O{sub 3} foils, the transmission of 420 nm light gained by using nano-particles all but disappears as the foil thickness is increased beyond about 0.2 mm, a practical scintillator thickness. This was not immediately apparent from the preliminary study since no foils thicker than about 0.04 mm were produced. Initially it was believed that the failure to see an improvement by using nano-particles for the LiFZnS foils was caused by the clumping of the particles in Toluene due to the polarity of the ZnS particles. However, we found, much to our surprise, that nano-particle ZnS alone in polystyrene, and in Epoxy, had worse light transmission properties than the micro-particle foils for equivalent thickness and density foils. The neutron detection measurements, while disappointing, are attributable to our inability to procure or fabricate Bulk Doped ZnS nanoparticles. The cause for the failure of nano-particles to improve the scintillation light, and hence improved neutron detection efficiency, is a fundamental one of light scattering within the scintillator. A consequence of PartTec's documentation of this is that several concepts for the fabrication of improved {sup 6}LiFZnS scintillators were formulated that will be the subject of a future SBIR submission.