Unlocking the Core Geometry of High-Efficiency Copper Iodide Cluster Scintillators

Wentao Wu^a^,^b, Omar Mohammed^a^,^b

^aDivision of Physical Science and Engineering (PSE), King Abdullah University of Science and Technology (KAUST), Physical Sciences and Engineering Division (PSE), Thuwal, 23955, Saudi Arabia

^bCenter for Renewable Energy and Storage Technologies (CREST), Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST), Thuwal 23955–6900, Kingdom of Saudi Arabia.

Proceedings of Emerging Light Emitting Materials 2026 (EMLEM26)

Kallithea, Greece, 2026 September 20th - 23rd

Organizers: Maryna Bodnarchuk, Grigorios Itskos and Maksym Kovalenko

Oral, Wentao Wu, presentation 006
Publication date: 8th July 2026

Copper(I) halide-based emitters have recently garnered significant attention for their potential in X-ray imaging applications owing to their efficient emission, facile synthesis and low toxicity.[1-3] While several strategies have been proposed to improve scintillation efficiency in these systems,[4-6] the critical role of Cu–I cores—particularly during ultrafast energy conversion and transport—has received limited attention. In this work, we introduce a unified ligand strategy to construct a series of zero-dimensional copper(I) iodide clusters, including a Cu1I1 monomer, Cu2I2 rhomboid dimer, and Cu4I4 cubane tetramer, all exhibiting near-unity photoluminescence quantum yield (𝜙PL). This approach enables a systematic investigation of how core architecture governs radioluminescence (RL) behavior and efficiency beyond 𝜙PL. Our results demonstrate that the core geometry has a strong influence on both thermal stability and exciton relaxation pathways. Notably, low-temperature PL–RL differences uncover a previously unrecognized exciton relaxation channel intrinsic to the Cu4I4 cubane cluster, allowing a fraction of excitons to directly populate the ³CC state. This process confines exciton generation, transport, and radiative recombination within the Cu–I cubane, thereby potentially increasing the exciton transfer efficiency and enhancing scintillation efficiency. These findings provide critical insights into the fundamental scintillation mechanisms and structure–property relationships of Cu–I clusters, establishing core geometry as a key design principle for the development of next-generation, high-performance scintillators.

References:

[1] Zhu, K.; Reid, O.; Rangan, S.; Wang, L.; Li, J.; Antony Jesu Durai, K.; Zhou, K.; Javed, N.; Kasaei, L.; Yang, C.; Li, M.; Sun, Y.; Tan, K.; Cotlet, M.; Liu, Y.; Feldman, L. C.; O’Carroll, D. M.; Zhu, K.; Li, J., Dual interfacial H-bonding-enhanced deep-blue hybrid copper–iodide LEDs. Nature 2025, 643, 1246–1254.

[2] Liu, W.; Fang, Y.; Li, J., Copper Iodide Based Hybrid Phosphors for Energy‐Efficient General Lighting Technologies. Adv. Funct. Mater. 2018, 28 (8), 1705593.

[3] Troyano, J.; Zamora, F.; Delgado, S., Copper(i)-iodide cluster structures as functional and processable platform materials. Chem. Soc. Rev. 2021, 50 (7), 4606-4628.

[4] Wu, W.; Lin, S.; Wang, J.-X.; Xu, Y.; Tengyue He; Zhou, Y.; Yuan, P.; Maity, P.; Nadinov, I.; Thomas, S.; Huang, R.; Castro, C. S. P. D.; Yin, J.; Alshareef, H. N.; Bakr, O. M.; Mohammed, O. F., Enhanced X-ray luminescence in one-dimensional Cu–I coordination polymers via ligand halogen engineering. Chem 2025, 0 (0), 102401.

[5] Hu, X.; Yuan, X.; Yang, J.; Liu, G.; Xu, L.; Zhang, S.; Wang, Z.; Ren, Y.; Gong, J.; Wang, J.; Wu, K.; Lu, L.; Wu, X.; Wei, C.; Wang, S.; He, T.; Wang, J. X.; Mohammed, O. F.; Zeng, H.; Li, X., Thallium-Doping-Modulated Photon Emission and Scintillation Performance in Cs(3)Cu(2)I(5) Nanocrystals. Nano Lett. 2025, 25, 10680−10689.

[6] Peng, Q. C.; Si, Y. B.; Yuan, J. W.; Yang, Q.; Gao, Z. Y.; Liu, Y. Y.; Wang, Z. Y.; Li, K.; Zang, S. Q.; Zhong Tang, B., High Performance Dynamic X-ray Flexible Imaging Realized Using a Copper Iodide Cluster-Based MOF Microcrystal Scintillator. Angew. Chem. Int. Ed. Engl. 2023, 62 (40), e202308194.

Acknowledgements:

This work was supported by the King Abdullah University of Science and Technology.

nanoGe is a prestigious brand of successful science conferences that are developed along the year in different areas of the world since 2009. Our worldwide conferences cover cutting-edge materials topics like perovskite solar cells, photovoltaics, optoelectronics, solar fuel conversion, surface science, catalysis and two-dimensional materials, among many others.

MATSUS

Previously nanoGe Spring Meeting (NSM) and nanoGe Fall Meeting (NFM), MATSUS is a multiple symposia conference focused on a broad set of topics of advanced materials preparation, their fundamental properties, and their applications, in fields such as renewable energy, photovoltaics, lighting, semiconductor quantum dots, 2-D materials synthesis, charge carriers dynamics, microscopy and spectroscopy semiconductors fundamentals, etc.

International Conference on Hybrid and Organic Photovoltaics

International Conference on Hybrid and Organic Photovoltaics (HOPV) is celebrated yearly in May. The main topics are the development, function and modeling of materials and devices for hybrid and organic solar cells. The field is now dominated by perovskite solar cells but also other hybrid technologies, as organic solar cells, quantum dot solar cells, and dye-sensitized solar cells and their integration into devices for photoelectrochemical solar fuel production.

Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics

The main topics of the Asia-Pacific International Conference on Perovskite, Organic Photovoltaics and Optoelectronics (IPEROP) are discussed every year in Asia-Pacific for gathering the recent advances in the fields of material preparation, modeling and fabrication of perovskite and hybrid and organic materials. Photovoltaic devices are analyzed from fundamental physics and materials properties to a broad set of applications. The conference also covers the developments of perovskite optoelectronics, including light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.

International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics

The International Conference on Perovskite Thin Film Photovoltaics Perovskite Photonics and Optoelectronics (NIPHO) is the best place to hear the latest developments in perovskite solar cells as well as on recent advances in the fields of perovskite light-emitting diodes, lasers, optical devices, nanophotonics, nonlinear optical properties, colloidal nanostructures, photophysics and light-matter coupling.