Preparation Of Rare Earth Doped ZnWO₄ Photonic Crystal And Spectrum Conversion Material And Their Applying Exploration

Since the photonic crystal was introduced in 1987, of whose special structure and physical properties have attracted considerable scientific and technological interests. Modulation periodically of photonic crystal on luminescent materials opens up a new space in the filed of photonicelectronics. Scintillation nuclear radiation detector is widely applied in radiation detection owing to high stopping power, strong ability of resistance to radiation damage, little temperature influence, high luminescence efficiency and so on. The development rapidly of high-energy physics and nuclear medicine puts forward higher demand for radiation detection. At present, the bottleneck of restricting performance improvement of radiation detector appears on scintillator. Therefore improving the optical performance of the scintillator is the key to improve the detection capability of a scintillation detector. Based on this, the thesis launches related researches including rare earth doped Zn WO₄ inverse opal photonic crystal scintillator and spectral conversion material. The detailed research contents and obtained results were shown as follows:Fabricate Zn WO₄ and Zn WO₄:Eu³⁺ inverse opal photonic crystal（IOPC） scintillator based on polymethyl methacrylate（PMMA） templates assited vertical deposition self-assenmly method. Photonic crystal is innovatively applied into Zn WO₄-based scintillation materials. Compared to powder reference sample, the energy transfer from tungstate groups to Eu³⁺ ions is more efficient in IOPC, which is attributed to the decreased non-radiative transition and the suppressed spontaneous emission rate. Meanwhile, modulations of photonic bandgap on wideband of tunstate group and sharp emission of Eu³⁺ ion are observed. In addition, when the concentration of Eu³⁺ is up to 3%, white light emission is obtained. It is important to emphasize that the luminescent quantum efficiency of the IOPC samples is remarkably enhanced and the quantum efficiency of Zn WO₄ IOPCs without doping is as high as 70%, which is almost the optimum among various Zn WO₄-based phosphors reported before. The increase of quantum efficiency improves the detection performance of scintillator radation detector, furthmore, photonic crystal with particular structure that the medium having different refractive indices are arranged periodically result in the decrease of effective refractive index of Zn WO₄ scintillator, which increase the light collection efficiency of scintillator radation detector.Put forward a conception of the spectral conversion material is applied in to the scintillaor. Up-conversion nanomaterial Na YF₄@Na YF₄:Yb³⁺,Er3+ was synthesized according to a solvothermal method, of whose surface morphology and spectra properties are analyzed in brief and then discuss elaborately up-conversion mechanism and its application in radiation detection.To sum up, the thesis present the preparation of rare earth doped oxide photonic crystal luminescence material, which is innovatively applied into radiation detector and analysize the application feature of improving nuclear radiation detector.