Bright and Durable Copper-Iodide-Based Nanowire Scintillators

Abstract

The increasing demand for high-speed X-ray imaging requires scintillators with high light yield, rapid decay, and structural stability. Metal halide nanowires (NWs) have emerged as promising candidates due to their distinctive optical properties, high surface-area-to-volume ratio, high light yield, and high spatial resolution. However, their practical application is hindered by complex synthesis routes and performance degradation during the liquid–solid phase transition. Here, using CsCu₂I₃ NWs as a model system, we develop a streamlined low-temperature crystallization synthesis method and further introduce a surface protective agent strategy that significantly enhances scintillation performance. Through the use of tailored protective agents, the photoluminescence quantum yield of NWs increases from 12.78% to 21.65%, while the X-ray light yield improves by approximately ninefold, reaching ∼77,500 photons MeV⁻¹. The optimized scintillator achieves a low detection limit of 59.20 nGy_air·s⁻¹, which is approximately 93-fold lower than the typical dose rate of standard medical X-ray diagnostics. Identical SPA treatment delivers uniform luminescence improvement across zero-and one-dimensional copper halide systems, confirming the generalizable regulatory effect of the proposed ligand coordination framework. This efficient and scalable approach not only advances nanowire-based scintillators but also provides a generalizable pathway for stabilizing solution-processed nanomaterials and accelerating their commercial adoption.

Keywords

copper(I)-iodide / detection limit / light yield / nanowire / scintillator

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