Diamond Composite With Embedded Yag:Ce Nanoparticles As A Source Of Fast X-Ray Luminescence In The Visible And Near-Ir Range

The diamond composite materials with embedded yttrium-aluminum garnet doped with cerium (YAG:Ce) nanoparticles have been produced by microwave plasma-assisted chemical vapor deposition (CVD). Nanoparticles were synthesized by co-precipitation from an aqueous solution while CVD diamond served as the transparent matrix with high thermal conductivity, hardness, and resistivity to radiation damage. The composite films show high-intensity X-ray luminescence (XRL) with a broad band peaking around the wavelength of 550 nm (5d -> 4f transition in Ce3+ ion), and a narrow peak of silicon-vacancy (SieV) centers at 738 nm. The characteristic decay time was measured at tau(Ce) < 50 ns for cerium emission and at tau(SiV similar to 1) ns for SieV centers. Excitation spectra of both luminescence types measured near yttrium K-edge (17.1 keV) show a strong correlation, attributed to the excitation of SieV luminescence by photoelectrons ejected from YAG:Ce nanoparticles. The discovered phenomenon suggests a new way to control X-ray visualization by luminescent diamond composites for fast X-ray detectors and screens. (C) 2020 Elsevier Ltd. All rights reserved.