Speaker
Description
The development of high-quality gadolinium (Gd) targets is of significant interest for nuclear physics exper-iments and radioisotope production [1,2], where precise control over thickness, uniformity, and chemical composi-tion is essential. Conventional fabrication techniques often face limitations related to cost, scalability, and composi-tional homogeneity. In this work, we investigate polymer-assisted deposition (PAD) as a versatile and cost-effective method for producing Gd-based thin film targets with controlled properties.
The PAD approach [3] relies on the complexation of Gd³⁺ ions with a water-soluble polymer such as poly-ethylenimine (PEI) to form a stable precursor solution. This strategy enables homogeneous distribution of metal ions at the molecular level while preventing premature precipitation. The resulting solution is deposited onto graphite substrates, using a spin-coating technique. Graphite substrates are particularly attractive for nuclear applications due to their low atomic number and excellent thermal conductivity, allowing efficient heat dissipation under high irradia-tion fluxes. Subsequent thermal treatment leads to the decomposition of the polymer matrix and the formation of dense, uniform gadolinium oxide (Gd₂O₃) films.
Key parameters influencing the quality of the deposited targets were systematically investigated, including the PEI-to-metal ratio, solution pH (adjusted using mild buffering systems such as acetate buffers), and thermal processing conditions. Control of pH was found to be critical in balancing the protonation state of the polymer and the stability of Gd(III) complexes, directly impacting film homogeneity and reproducibility. Thermal treatment pro-tocols were optimized to ensure complete removal of organic residues while minimizing film cracking and preserving adhesion to the substrate.
The resulting films were characterized using complementary techniques, including scanning electron microscopy (SEM) and Rutherford backscattering spectroscopy (RBS). These analyses indicate the formation of Gd₂O₃ layers with relatively uniform thickness and good adhesion, with no significant cracking observed under the investigated conditions. The PAD method shows acceptable reproducibility and scalability, suggesting its potential as an alternative to conventional target fabrication techniques.
This study explores the application of PAD to the preparation of gadolinium-based targets on graphite sub-strates for nuclear applications. Future work will focus on extending this approach to enriched isotopic materials and further evaluating target performance under irradiation conditions.
[1] J. M. Pyles et al., ACS Omega, 10(28), 30335 (2025).
[2] M. Bouteculet et al., Applied Radiation and Isotopes, 213, 111485 (2024).
[3] Q. X. Jia et al., Nature Materials, 3(8), 529 (2004).