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Отримано композитний фотокаталiзатор, що складається з шару зародкiв ZnO з n-типом електропровiдностi, "наноквiтiв" ZnO з n-типом електропровiдностi та поруватого кремнiю з p-типом електропровiдностi. Дослiджено фотодеґрадацiю барвника з використанням композитних фотокаталiзаторiв на основi тонких плiвок i "наноквiтiв". Використання "наноквiтiв" ZnO дало змогу полiпшити фотокаталiтичнi властивостi композиту.Ключовi слова: композит, фотокаталiзатор, фотодеґрадацiя, оксид цинку, поруватий кремнiй.

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The photoluminescence spectra of ZnO nanorods grown by the hydrothermal method were investigated. In the nanostructures the neutral donor bound excitons dominate in the ultraviolet (UV) region of the photoluminescence spectrum at liquid helium temperature. The presence of the band two electron satellite transitions (TES) of the donor bound excitons allow to determine the donor binding energies ED of about 53 meV. On the basis of the measurements performed at different temperatures the thermal activation energy of the luminescence quenching (Ea  14 meV) was obtained.

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Light emitting diodes (LEDs) structures based on p-GaN lm/n-ZnO nanorods quasiarray heterojunction were fabricated. ZnO nanostructures were grown on the p-type GaN templates using two dierent methods. The turn-on voltages of ZnO/GaN heterojunctions based on ZnO nanorods grown using the gas-transport reaction and hydrothermal methods were equal to 3.2 V and 6.5 V, respectively. The diode-ideality factors were estimated to be of around 45 and 36 for the samples with ZnO nanorods grown using the method of the gas-transport reaction and the hydrothermal method, respectively. The large values of the ideality factors can be explained by a high density of trap states and quality of the contacts with the p − n junctions. The electroluminescence (EL) spectra of LEDs with ZnO nanorods grown by the gas-transport reaction and hydrothermal methods were approximated by four and three Gaussians, respectively. On the basis of the X-ray diraction (XRD), electrical and optical studies data, one can conclude that the emission peaks at 389391, 410412, 436438 and 502 nm correspond to the near-band-edge (NBE) recombination in ZnO, interface carriers recombination in ZnO/GaN junction, the electrons transition from GaN conduction band to Mg 2+ doping level, and to the emission from the defect levels in ZnO, respectively. The LED based on ZnO nanorods synthesized using the hydrothermal method emitted a more pure ultraviolet (UV) light.