ИСТИНА

Тhe purpose of this work was to synthesize non-luminescent PAAO and study the PL of the test analyte in the pores of the samples. Rhodamine B was chosen as the analyte.We will use the following designations for the samples, prepared in sulfuric acid: S5 (initial), S5-R1 (with Rhodamine B 10−5 M), S5-R2 (with Rhodamine B 10−6 M), S5-R3 (with Rhodamine B 10−7 M) and for the samples, prepared in selenium acid: Se5 (initial), Se5-R1 (with Rhodamine B 10−5 M), Se5-R2 (with Rhodamine B 10−6 M), Se5-R3 (with Rhodamine B 10−7 M).It is evident that the average pore diameter of the samples varies from 9 to 15 nm. Quite a large deviation in size can be explained by the elongated shape of some samples, probably due to the merging of two "seed" pores into one during the formation of PAAO. The thickness of the porous layer is 7.5 μm. No structural changes are observed when the dye is applied. Also, no large dye clusters or films are observed on the oxide surface, indicating that the dye was adsorbed exclusively on the sample surface. The samples acquire a stable pinkish tint that is not removed by washing.Raman spectroscopy studies showed that the samples had an amorphous structure.The initial PAAO (S5 and Se5) did not luminesce. Therefore, the obtained PAAO samples can be used for the analysis of the PL of the analyte (dye) in the pores of PAAO. S5-R1 and Se5-R1 samples demonstrated intense PL of rhodamine B in the range of 530-680 nm with a PL maximum at 573 nm.The PL intensity of the dye increased sharply starting from the Rhodamine B concentration of 10-5 M in the samples synthesized both in sulfuric acid and in selenium acid. At low dye concentrations (10-7-10-6 M), the PL intensity was approximately the same for both types of samples.