Title: Neutron sensing at spallation neutron sources by SERS

Authors: Sebastiano Trusso (Istituto per i Processi Chimico-Fisici, CNR, Messina), Giulia Festa (Centro Ricerche Enrico Fermi, Roma, Italy), Claudia Scatigno (Centro Ricerche Enrico Fermi, Roma), Giovanni Romanelli (Dipartimento di Fisica & NAST Centre, Università degli Studi di Roma “Tor Vergata”), Anna Piperno (Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina), Rosina Celeste Ponterio (Istituto per i Processi Chimico-Fisici, CNR, Messina).

Published on Applied Surface Science Volume 651, 1 April 2024, 159186

DOI https://doi.org/10.1016/j.apsusc.2023.159186

Abstract:

Neutron detectors are paramount in many applications, from medical science to homeland security and aerospace. A miniaturized solid-state device based on a nanostructured-gold thin film grown by pulsed laser ablation under deposition-controlled conditions and functionalized with a monolayer of 4-mercaptophenyboronic acid (4-MPBA) was fabricated as a neutron dose detector. The device is tested with slow neutron detection in the thermal and epithermal energy range at ISIS spallation neutron source (UK). After the neutron irradiation, 4-MPBA is converted into thiophenol (TP), and the chemical modification is monitored by the intensity of related vibrational bands at 1586 cm⁻¹ (4-MPBA) and 1574 cm⁻¹ (TP). The latter are used as a vibrational signature of the absorbed dose by surface-enhanced Raman spectroscopy (SERS). The conversion of 4-MPBA to TP is due to the loss of the boron-containing group after the absorption of a slow neutron by ¹⁰B isotope. The I₁₅₇₄/I₁₅₈₆ ratio is used to estimate the ratio of ¹⁰B nuclei absorption reactions due to the thermal and epithermal contributions. It is proposed for the development of neutron dosimetry for nuclear medicine, aerospace, and security applications.