Luminescent diamond composites

Figures & data

Figure 1. The scheme of diamond composite preparation by embedding RE-based nanoparticles (EuF₃) between two microcrystalline diamond layers on the silicon substrate [66].

Figure 2. SEM image of the cross-section of the diamond film with embedded EuF₃ particles in the middle of the film (a). EDX mapping of elements across the same cross-section (b): green layer – silicon, blue layer – carbon, purple dots – europium (also shown by the arrow) [66].

Figure 3. The high-resolution PL spectrum (473 nm, R.T.) for the EuF₃ component in the composite film (c), and PL decay of Eu related peak for EuF₃ powder (red – 617 nm, blue – 612 nm, orange – 590 nm) and for the EuF₃ - diamond composite (black line) after switching off the laser excitation. Red dotted lines show data fits with single exponential decay [66].

Figure 4. (a) XRL spectrum of the pristine NaGdF₄: Eu powder, (b) XRL spectra of composite Diamond-RE films with the increasing total concentration of NaGdF₄: Eu nanoparticles by increasing the volume of applied 30 mg/ml suspension: x1 - 1 drop of the suspension, x2 - 2 drops, x3 - 3 drops, Inset (I) shows the series of peaks near 612 nm in a narrow wavelength range; Inset (II) – dependence of integrated XRL intensity in 600–620 nm range on the concentration of NaGdF₄: Eu nanoparticles (dashed line – the guide for the eye) [102].

Figure 5. (a) XRL spectrum of the obtained “Diamond-YAG:Ce” composite at RT; (b) excitation spectra of cerium 5d → 4f luminescence (550 nm) and SiV luminescence (738 nm) across the K-edge of yttrium; (c) luminescence decay kinetics of Ce³⁺ (530 and 600 nm) and SiV (738 nm) centers in the obtained “Diamond-YAG:Ce” composite material, excitation 19 keV, RT. Inset in (b) – normalized spectra of Ce³⁺ and SiV emission. The results in (c) for the best-suited fitting components are shown near experimental lines: the decay times, and the relative contribution of each component [109].

Figure 6. Photographs of the “Diamond-GSAG:Ce” composite membranes (2 drops of Gd_2.73Ce_0.02Sc_0.5Al_4.75O₁₂ dispersion) under standard indoor lighting (a) and in the dark under X-ray radiation (b), as well as the X-ray luminescence spectrum of the composite (1 and 2 drops of Gd_2.73Ce_0.02Sc_0.5Al_4.75O₁₂, accordingly). Note (b) white speckles as artifacts caused by the exposure of photosensitive elements in the camera to X-rays. The inhomogeneity of luminescence in (b) is due to the inhomogeneity of the distribution of GSAG: Ce particles in the composite [113].

Figure 7. (a,b) SEM images of diamond/SiC composite film deposited in CH₄ (4 sccm)/H₂ (400 sccm) mixture with added TMS gas (5 sccm). The inset corresponds to a cross-sectional SEM image. (c) Photoluminescent spectra of diamond/SiC composite films grown with different TMS gas flows, sample 1#: 0 sccm; sample 2#: 5sccm; sample 3#: 15 sccm; sample 4#: 30 sccm. Not a strong SiV PL peak at 738 nm. The presence of the SiV peak in sample #1 (no TMS) is caused by the etching of Si substrate with hydrogen plasma during the process of film deposition. The spectra are recorded under the excitation of a 532 nm laser [120].

Figure 8. (a) SEM image (SE mode) of polycrystalline diamond-Ge film grown by an MPCVD in CH₄-H₂-GeH₄ mixture at substrate temperature 800 °C. Larger grains are Ge crystallites. (b) PL spectra with GeV band around 602 nm for the composites produced at different substrate temperatures of 750–950 °C. The PL spectra are normalized to the diamond Raman peak area and shifted vertically for clarity [118].

Sedov VS, Kuznetsov SV, Ralchenko VG, et al. Diamond-EuF3 nanocomposites with bright orange photoluminescence. Diam Relat Mater. 2017;72:47–52.

 Web of Science ®Google Scholar

Sedov V, Kouznetsov S, Martyanov A, et al. Diamond–rare earth composites with embedded NaGdF4: Eu nanoparticles as robust photo-and X-ray-Luminescent materials for radiation monitoring screens. ACS Appl Nano Mater. 2020;3(2):1324–1331.

 Web of Science ®Google Scholar

Sedov V, Kuznetsov S, Kamenskikh I, et al. Diamond composite with embedded YAG: Ce nanoparticles as a source of fast X-ray luminescence in the visible and near-IR range. Carbon. 2021;174:52–58.

 Web of Science ®Google Scholar

Kuznetsov SV, Sedov VS, Martyanov AK, et al. Cerium-doped gadolinium-scandium-aluminum garnet powders: Synthesis and use in X-ray luminescent diamond composites. Ceram Int. 2022;48(9):12962–12970.

 Google Scholar

Yang B, Li H, Yu B, et al. Bright silicon vacancy centers in diamond/SiC composite films synthesized by a MPCVD method. Carbon. 2021;171:455–463.

 Web of Science ®Google Scholar

Ralchenko V, Sedov V, Martyanov A, et al. Diamond-germanium composite films grown by microwave plasma CVD. Carbon. 2022;190:10–21.

 Web of Science ®Google Scholar