Aktivētu AlN pulveru luminiscence

Abstract

Darbā tika pētīta fotoluminiscence un tās ierosmes spektri dažādiem AlN pulveriem: AlN nanopulverim, AlN pulveriem dopētiem ar Tb vai Mn (izgatavotiem Rīgas Tehniskās Universitātes Neorganiskās ķīmijas institūtā) ar mērķi izgatavot balto gaismu starojošu sastāvu, kuru varētu pielietot luminiscentās lampās (LL). Tika konstatēts, ka minēto pulveru luminiscence veido platas joslas zilajā, zaļajā un sarkanajā daļā, kas kopā atbilst baltās gaismas starojumam. Tika atrasts optimālais pulveru maisījumu sastāvs, kas staro balto gaismu. Pētot atsevišķo pulveru luminiscences ierosmes spektrus, tika konstatēts, ka visos paraugos luminiscences joslas var tikt ierosinātas ar 240 nm – 265 nm un 200 nm ultravioleto (UV) gaismu, kas atbilst Hg starojumam, ko lieto luminiscentās lampās. Tika izpētīta arī polimetilmetakrilāta (PMMA) un etilēnvinilacetāta (EVA) luminiscence, to ierosmes un absorbcijas spektri, lai varētu izveidot matricu jaukto pulveru fiksēšanai. Matricas izveidei tika izvēlēts PMMA mat

The spectral characteristics of different AlN powders: AlN nanopowder, AlN doped with Tb or Mn were investigated (materiāls were synthesized at RTU NĶI). The aim of this work is to create a new white light source from these materials with appropriate spectral distribution so that it could be used in luminescent lamps. It was observed that these materials have wide luminescence bands in blue, green and red part of the spectrum and that together they can form a white light source. An optional mixture of these powders was created so that the luminescence spectrum of it would correspond with white light. It was found that separate powders can be excited with 240 nm – 265 nm and 200 nm UV light and these excitation bands corresponds with Hg emission spectrum used in luminescent lamps. The spectral characteristics of PMMA and EVA were also studied. It was found that the PMMA better conforms to its aim – fixing the newfound white light powder in matrix. The PMMA itself radiates in the blue p