Alpha spectroscopy substrates based on thin polymer films

Degradable and Dissolvable Thin-Film Materials for the Applications of New-Generation Environmental-Friendly Electronic Devices

The environmental pollution generated by electronic waste (e-waste), waste-gas, and wastewater restricts the sustainable development of society. Environmental-friendly electronics made of degradable, resorbable, and compatible thin-film materials were utilized and explored, which was beneficial for e-waste dissolution and sustainable development. In this paper, we present a literature review about the development of various degradable and disposable thin-films for electronic applications. The corresponding preparation methods were simply reviewed and one of the most exciting and promising methods was discussed: Printing electronics technology. After a short introduction, detailed applications in the environment sensors and eco-friendly devices based on these degradable and compatible thin-films were mainly reviewed, finalizing with the main conclusions and promising perspectives. Furthermore, the future on these upcoming environmental-friendly electronic devices are proposed and prospected, especially on resistive switching devices, showing great potential applications in artificial intelligence (AI) and the Internet of Thing (IoT). These resistive switching devices combine the functions of storage and computations, which can complement the off-shelf computing based on the von Neumann architecture and advance the development of the AI.

Anion-exchange polymer filament coating for ultra-trace isotopic analysis of plutonium by thermal ionization mass spectrometry

A new sample loading procedure was developed for isotope measurements of ultra-trace amounts of Pu with thermal ionization mass spectrometry (TIMS) that is based on a polymer thin film architecture. The goals were to simplify single filament TIMS sample preparation for Pu, while preserving the sensitivity and accuracy of the resin bead loading method, and to eliminate sample losses experienced with the bead loading method. Rhenium filaments were degassed, dip-coated with a thin (~ 120 nm) hydrophobic base layer of poly(vinylbenzyl chloride) (PVBC), and spotted with an aqueous solution comprising triethylamine-quaternized PVBC and diazabicyclo[2.2.2]octane crosslinker. This procedure formed a toroidal, hydrophilic anion-exchange polymer spot surrounded by the hydrophobic base polymer. The thin film-coated filaments were direct loaded with 10 pg of New Brunswick Laboratory certified reference material (NBL CRM) 128 from a 9 M HCl matrix. Aqueous sample droplets adhered to the anion-exchange polymer spot, facilitating sample loading. Toroidal spots with a thickness of 20-30 µm generated the highest sample utilization, surpassing the sample utilization of the standard bead loading method by 175%. Measured isotopic ratios were in good agreement with the certified value of the ²³⁹Pu/²⁴²Pu ratio for NBL CRM 128. The use of dimpled filaments further aided sample loading by providing a well-shaped substrate to deposit the sample droplet. No sample losses were experienced with the thin film loading method over 65 sample analyses. Finally, polymer coatings suppressed filament aging under atmospheric conditions, enabling the bulk production of filaments with adequate shelf life for future analyses.

Rapid Sample Preparation for Alpha Spectroscopy with Ultrafiltration Membranes

This contribution describes a rapid, fieldable alpha spectroscopy sample preparation technique that minimizes consumables and decreases the nuclear forensics timeline. Functional ultrafiltration membranes are presented that selectively concentrate uranium directly from pH 6 groundwater and serve as the alpha spectroscopy substrate. Membranes were prepared by ultraviolet grafting of uranium-selective polymer chains from the membrane surface. Membranes were characterized by Fourier-transform infrared spectroscopy before and after modification to support functionalization. Membrane performance was evaluated using uranium-233 or depleted uranium in both deionized and simulated groundwater at pH 6. Functionalized membranes achieved peak energy resolutions of 31 ± 2 keV and recoveries of 81 ± 4% when prepared directly from pH 6 simulated groundwater. For simulated groundwater spiked with depleted uranium, baseline energy resolution was achieved for both isotopes (uranium-238 and uranium-234). The porous, uranium-selective substrate designs can process liters per hour of uranium-contaminated groundwater using low-pressure (<150 kPa) filtration and a 45 mm diameter membrane filter, leading to a high-throughput, one-step concentration, purification, and sample mounting process.