Font Size: a A A

Several Oxide (Sulfide) Nanomaterials: Preparation And Optical Properties

Posted on:2007-03-29Degree:DoctorType:Dissertation
Country:ChinaCandidate:S F WangFull Text:PDF
GTID:1101360185484173Subject:Materials science
Abstract/Summary:PDF Full Text Request
Nanoscaled luminescent materials have found wide applications in many fields, such as display, illumination, photo-electronic devices. In order to explore novel luminescent systems with high efficiency, in this thesis, we chose and synthesized several oxide/sulfide nanomaterials via different methods and studied their luminescent properties systemically by introducing different dopant ions as well as their morphology-dependent optical properties.In Chapter 1, we briefly introduced the conceptions, the preparation methods, the unique structural characteristic and properties of nanomaterials. Also, we introduced the corresponding theory of the luminescent nanomaterials.In Chapter 2, we studied the preparation and luminescent properties of nanocrystalline ZrO2 and Eu2O3. A simple precipitation method has been employed for the synthesis of ZrO2 nanocrystals. By introducing Pb2+ and Dy3+ ions into ZrO2, we firstly studied the luminescent properties of the doped system. Red emission at 630nm of Pb2+ and blue (480nm) and yellow emission (575nm) of Dy3+ can be observed. Because of the cross-relaxation process of luminescent centers, luminescent quenching occurs with the increase of the dopant concentrations. The optimal values for Pb2+ and Dy3+ are 5% and 2%, respectively. With increasing calcining temperature, the content of chlorine in the host decreases rapidly for evaporation, which induces the decrease of the luminescent intensity. Er3+ was introduced as a co-activator ion into the ZrO2: Mn2+ nanocrystals. Due to the energy transfer of Er3+→Mn2+, the emission intensity of Mn2+ was increased greatly. By adjusting the concentration of the dopant, the optimal value for Er3+ was determined to be 0.3%. By using Ca2+ as a stabilizer, we synthesized ZrO2 nanocrystals at a relatively lower temperature (400℃) via a combustion process. The phase transformation from monoclinic (m) to...
Keywords/Search Tags:Nanomaterials, Luminescence, Doping, Synthesis, Surfactant
PDF Full Text Request
Related items