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This article presents the study of the electrochemical deposition of zinc oxide from the non-aqueous solution based on dimethyl sulfoxide and zinc chloride into the porous silicon matrix. The features of the deposition process depending on the thickness of the porous silicon layer are presented. It is shown that after deposition process the porous silicon matrix is filled with zinc oxide nanocrystals with a diameter of 10-50 nm. The electrochemically deposited zinc oxide layers on top of porous silicon are shown to have a crystalline structure. It is also shown that zinc oxide crystals formed by hydrothermal method on the surface of electrochemically deposited zinc oxide film demonstrate ultra-violet luminescence. The effect of the porous silicon layer thickness on the morphology of the zinc oxide is shown. The structures obtained demonstrated two luminescence bands peaking at the 375 and 600 nm wavelengths. Possible applications of ZnO nanostructures, porous and continuous polycrystalline ZnO films such as gas sensors, light-emitting diodes, photovoltaic devices, and nanopiezo energy generators are considered. Aspects of integration with conventional silicon technology are also discussed

Graphitic carbon nitride (g‐C3N4) is synthesized by thermal decomposition of thiourea and subsequent in situ polymerization of the products in the oxygen‐containing ambient at 450–625 °C and studied with scanning electron microscopy, X‐ray diffraction, energy‐dispersive X‐ray spectroscopy, Fourier‐transform infrared spectroscopy, and photoluminescence techniques. The synthesized material contains oxygen at a concentration increasing with the processing temperature from 4.8 to 9.8 at %. The photoluminescence peak is found to be red‐shifted with the temperature increased to 575 °C becoming then blue‐shifted at higher temperatures. The observed red‐shift of the photoluminescence peak is supposed to be caused by band‐gap narrowing in g‐C3N4 doped by oxygen while its recovery behavior is controlled by thermally induced oxygen‐assisted disruption of sp2 bonds in C‐N π‐orbital conjugated system of tri‐s‐triazine units building polymer sheets in g‐C3N4.

We developed and studied facile synthesis of graphitic carbon nitride in macroporous silica glass matrix. Melamine was used as a precursor. The synthesis was performed in a closed air ambience at 400–600∘C. It was found that the synthesized material was characterized with a broadband room-temperature photoluminescence in the range of 350–750[Formula: see text]nm with the peak shifting from to 445[Formula: see text]nm to 702[Formula: see text]nm when the temperature of the synthesis was increased from [Formula: see text]C to [Formula: see text]C while the intensity of the luminescence was decreased. The nature of the luminescent centers and possible applications of the synthesized material are discussed.