Nanoscale Gd₂O₂S:Tb Scintillators for High-Resolution Fluorescent Imaging of Cold Neutrons

Abstract

Cold neutron has a strong ability to penetrate metal materials and identify light elements, making it an ideal nondestructive testing technique for detecting cracks, bubbles, or other defects in metals. However, the low imaging resolution and detection efficiency of scintillators limit the application of cold neutron technology in imaging. The particle size and luminescence properties of scintillator materials have an important influence on the spatial resolution and detection efficiency of cold neutron radiography. Here, we report a series of NaF-doped Gd2O2S:Tb3+ (NaF-d-GOS:Tb) scintillators with adjustable particle size, which were prepared through a two-step method of solution precipitation followed by solid-phase vulcanization calcination. It was found that the NaF-d-GOS:Tb scintillators showed the highest quantum yield, reaching up to 62.94%. They were applied to fabricating cold neutron ultrathin screens. The resolution can reach 12 μm in the cold neutron imaging system. These NaF-d-GOS:Tb scintillators with excellent fluorescence facilitate the development of nondestructive testing techniques based on cold neutron imaging.

Controlled Synthesis of Terbium-Doped Colloidal Gd2O2S Nanoplatelets Enables High-Performance X-ray Scintillators

“…This behavior was also observed previously in the Tb 3+ doped CeF 3 nanocrystals . The PL lifetime values obtained in this work are in agreement with previously reported values (0.7–1.3 ms) for bulk and nanocrystalline Gd 2 O 2 S:Tb phosphors. , It is worth noting that for a fixed Tb concentration, the reaction time has no significant effect on the PL lifetime and the PLQY of the NPLs (Figure S14).…”

“…Solution-processed nanocrystalline rare-earth oxysulfides (RE 2 O 2 S, including Gd 2 O 2 S) can be synthesized at relatively low temperatures using either water-based or organic solvent-based methods. ,, Synthesis using high-boiling point organic solvents offers better control over the oxygen and sulfur content compared to synthesis in water, which helps to avoid the formation of oxide impurity phases. , The colloidal synthesis of RE 2 O 2 S involves the use of high-boiling point organic solvents and surfactants such as oleic acid (OA) and oleylamine (OAm). Nanoplatelets (NPLs) are usually formed during the colloidal synthesis of RE 2 O 2 S, which can be attributed to their hexagonal crystal structure.…”

Stable Organic Antimony Halides with Near‐Unity Photoluminescence Quantum Yield for X‐Ray Imaging

“…[12][13][14][15][16] Historically, pure inorganic scintillators, such as NaI:Tl, CsI:Tl, Gd 2 O 2 S:Tb (GOS), Bi 4 Ge 3 O 12 (BGO), and Lu 1.8 Y 0.2 SiO 5 :Ce (LYSO), have been employed in the study of X-ray imaging owing to their high light yields. [17][18][19][20][21][22] However, these scintillators encounter some problems in the process of material preparation and practical use. For example, the humidity-sensitive nature of CsI:Tl hampers its long-term stability and persistent light output.…”

Toward “super-scintillation” with nanomaterials and nanophotonics

“…Following the first report of scintillation response in quantum dots (QDs) by Létant and Wang in 2006 [ 33 ], several other emerging materials platforms, low-dimensional platforms, have been proposed and evaluated including metal halide perovskites [ 34 ], [ 35 ], all inorganic perovskites [ 36 ], organic–inorganic layered perovskites, scintillating nanotubes [ 37 ], [ 38 ], lanthanide-doped nanoparticles [ 7 ], [ 10 ], and metal–organic frameworks [ 39 ], [ 40 ]. In addition to rare-earth doped nanoscintillators, various types of oxides [ 41 ], [ 42 ], halides [ 43 ], sulfides [ 44 ], and oxysulfides scintillating nanostructures [ 45 ] with varying refractive index have been designed and evaluated offering a tunable range of scintillation wavelength, morphology, decay lifetime, and radiation hardness. Despite a plethora of advantages including outstanding spectral range tunability and flexibility of design, nanoscintillators can suffer from low quantum yield originating from thermal quenching and large self-absorption compared to their bulk counterparts.…”