Light Emission From Pristine And Rare Earth Doped Nanoporous Organosilicate Films

The porous material's physicochemical properties can be attributed to its unique porous structure,which provides more active interfaces to load possible synergistic components.The porous structure allows the encapsulation of the guest material into the pores thanks to the chemical modification capability of its surface.It has led to the use of porous materials in various applications such as catalysis,adsorption,separation,energy storage and conversion,drug delivery and optics.Nanostructured luminescent materials and nanoscale luminescent devices have attracted attention due to their unique advantages.Rare earth doped nanoluminescent materials are a new class of luminescent nanomaterials with highly efficient visible light emission and increasing activity that have been discovered and actively studied in recent years.Based on this,this paper is devoted to investigate the performance of new rare-earth doped matrix materials,using polyoxyethylene lauryl ether(Brij30)as template agent to synthesize porous organosilicate glass(OSG)films,obtaining red light-emitting materials by doping with rare-earth Eu³⁺,and exploring the feasibility of enhancing the light-emitting properties of the materials by using 3-aminopropyltriethoxysilicate(APTES)as an auxiliary structural guiding agent.The feasibility of enhancing the luminescence of the materials by using 3-aminopropyltriethoxysilicon(APTES)as an auxiliary structural guide was explored.In this paper,we characterized the photoluminescence properties,pore structure and surface morphology of the synthesized porous organosilicate and investigated the photoluminescence mechanism and luminescence properties of the films before and after rare-earth doping.The main results obtained in the paper are as follows:1.Porous OSG films with microporous and mesoporous porosity of 0%-50%were prepared by sol-gel and spin-on deposition processes with different ratios of organic precursor solvents,using Brij30 as a template.The films were characterized in detail for different parameters,where the pristine films showed strong luminescence peaks in UV(295nm,370nm)and visible light(430nm).The luminescence peaks were related to defects in the films,and the photoluminescence phenomenon of the pristine films was further analyzed and studied by ICP etching experiments,which showed that the photoluminescence phenomenon of the films was related to-CH₃and-CH₂defects in the films,and the presence of oxygen defects was also involved in the photoluminescence process.2.An extended application study of the OSG films was conducted.The photo-chemical detection of sulfadiazine drug by the original OSG film was investigated.The photoluminescence property test showed that the film achieved real-time and rapid detection of sulfadiazine drug.3.Rare-earth doped OSG(Eu-OSG)materials were obtained by successfully doping Eu³⁺into OSG matrix using sol-gel method,and their luminescence properties were investigated.It was shown that the films have a red luminescence peak obviously located at 615nm and the doping of Eu³⁺changes the porosity of the films.The photoluminescence properties of Eu-OSG with different Eu³⁺doping concentrations were further investigated,and all the films showed strong Eu³⁺characteristic emission at 615nm.The optimal doping concentration of Eu³⁺was determined to be 12.1 wt%based on the sample with the strongest emission.Finally,the characteristic emission of Eu-OSG films at 615nm was sensitized by the antenna effect without radiative leap.