Electronic effects of aryl groups in modified polysilane liquid scintillator on its fluorescence-scintillation properties

Abstract

Radiation detection plays a crucial role in the construction and safe operation of nuclear facilities. Liquid scintillator is widely used in this field but its fluorescence-scintillation properties still require improvement to achieve high sensitivity detection at present. In this paper, a new liquid scintillator system is developed, which selects polysilane as the matrix, and aryl with electron repulsing/withdrawing groups as the grafting substituents. The conjugated structure between the Si–Si chain and the aryl scintillating group enables electron delocalization transfer, resulting in improved fluorescence emission spectra and scintillation sensitivity. Three aryl-grafted polysilanes with typical electron repulsing and withdrawing group are successfully synthesized by Grignard routes. The optical properties of the materials are evaluated through both molecular simulation and experimental measurements, to determine the electronic effect of aryl groups on the electron delocalization in modified polysilane scintillators. The scintillation count performance is also evaluated. In conclusion, polysilanes grafted with aryl groups can be utilized as a new type of liquid scintillator, and electron repulsing substituents could enhance the fluorescence-scintillation properties more effectively, which providing meaningful guidance for the further optimization of liquid scintillation composition.