1. Optimization of the efficiency of diamond based alpha-sensors for spectrometry in aqueous solutions
- Author
-
Tran, Quang Thuan, de Sanoit, Jacques, Pomorski, Michal, Mer-Calfati, Christine, Bergonzo, P., Laboratoire Capteurs et Architectures Electroniques (LCAE), Département Métrologie Instrumentation & Information (DM2I), Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Direction de Recherche Technologique (CEA) (DRT (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, ANR-11-SECU-0008,ActiFind,Traces d'émetteurs alpha dans les réseaux publics: de la détection directe en phase liquide à l'identification(2011), Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Laboratoire d'Intégration des Systèmes et des Technologies (LIST (CEA)), and D. Morelli (IEEE)
- Subjects
aqueous solutions ,spectroscopic stability ,current density ,diamond based alpha-sensors ,thin film ,alpha-particle spectroscopy in liquid media ,decontamination loops ,trace detection ,electrolytes ,doped diamond electrode ,[PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex] ,[CHIM.INOR]Chemical Sciences/Inorganic chemistry ,sensor area ,spectrometry ,liquid media ,anodic current ,alpha particle spectroscopy ,diamond ,sensor ,actinide collection ,alpha emitter species ,alpha-particle spectrometers ,boron doped nanocrystalline diamond film ,[PHYS.PHYS.PHYS-INS-DET]Physics [physics]/Physics [physics]/Instrumentation and Detectors [physics.ins-det] ,Terms-boron doped nanocrystalline diamond ,pH fine tuning ,electroprecipitation ,actinides electroprecipitation ,pH ,silicon device ,alpha-particle detection ,p-i-n diodes ,alpha activity ,precipitation loops ,decontamination ,silicon PIN diode alpha sensor ,electrochemical cell ,precipitation duration ,silicon radiation detectors ,alpha particle detection ,radioactivity ,electrodeposition ,ionizing radiation ,liquid solutions ,electrochemical electrodes ,precipitation (physical chemistry) ,optimization ,electrochemical deposition - Abstract
International audience; Alpha particles detection in liquid media remains challenging since alpha particles are self-absorbed by a few micrometers of liquid. Conventional techniques consist of electrodepositing alpha emitter species on a surface and counting alpha particles using e.g. a silicon device. We have presented a novel approach associating a boron doped nanocrystalline diamond film to a silicon PIN diode alpha sensor. In our devices, actinides collection is performed using a novel method based on electroprecipitation that can be carried out in the solution itself via the use of a doped diamond electrode. The device enables to directly probe both alpha activity as well as energy in liquid solutions. This work demonstrated that the detection of alpha particles is made feasible directly in liquid media. Here we present recent progress addressing the optimization of the actinides electroprecipitation step on the diamond/silicon sensor. The approach is based on the fine tuning of the pH of the electrolyte, the nature of the supporting electrolytes Na2SO4 and NaNO3, the geome1try of the electrochemical cell, the current density value, the precipitation duration and the sensor area. The efficiency of the deposition was significantly improved with efficiency values reaching for example up to 81.5 % for the electroprecipitation of 5.96 Bq of 241Am on the diamond/silicon sensor. The diamond/silicon sensor can be reused after measurement using fast decontamination at high yields ≥ 99 %: e.g. the deposited 241Am electroprecipitated layer can be rapidly removed by applying an anodic current (+ 2 mA/cm2 for 10 minutes) to the electrode in aqueous solution. The diamond/silicon sensor shows also very high spectroscopic stability after 30 cycles of sensing with precipitation/decontamination loops. This study demonstrated that alpha particles spectroscopy measurements could be practically performed, for the first time, in media composed of aqueous solutions after electrochemical deposition process, with detections limits reaching 0.24 Bq/L. We believe this can be of very high interest for alpha spectroscopy in liquids for trace detection.
- Published
- 2013
- Full Text
- View/download PDF