Fabrication of Hf_xSi_1−xO₂microparticle-loaded PVK-based plastic scintillators using the sol–gel method for high-energy X-ray detection at high counting rate

We synthesized Hf_xSi_1−xO₂microparticle-loaded poly(9-vinylcarbazole) (PVK)-based plastic scintillators using the sol–gel method for high-energy X-ray detection at a high counting rate. We successfully dispersed Hf_xSi_1−xO₂ microparticles into PVK-based plastic scintillators using hafnium dichloride oxide octahydrate and phenyltrimethoxysilane at Hf concentrations of up to 20 wt%. The scintillation decay time constants of the first component were approximately 2.0 ns. Loading Hf_xSi_1−xO₂ microparticles enhanced the detection efficiency for 67.41 keV X-rays. The detection efficiency per 1 mm thickness and light yield of the Hf-12.5 wt%-loaded plastic scintillator were, respectively, 2.0 and 1.1 times higher than those of EJ-256, a commercial Pb-5 wt%-loaded plastic scintillator. The decrease in light yield was successfully suppressed; the light yield was reduced by 44% even at a Hf concentration of 12.5 wt%. We successfully enhanced the high-energy X-ray detection characteristics of PVK-based plastic scintillators using the sol–gel method.