In Russian

Abstract

Photoelectrochemical properties have been studied of the electrodes based on the nanostructure containing TiO 2 nanotubes (NT–TiO 2 ) and CdSe films modified with graphene oxide (GO). Formation of TiO 2 nanotubes on titanium substrate increases the adhesion of deposited layer of polycrystalline CdSe. Such a modification of film by GO reduces the value of the cathode dark leakage current in an alkaline sulfide electrolyte, and the value of the open circuit voltage reaches 0.60 V. It has been determined the optimal amount of modifying agent GO ∼1%, which provides high photosensitivity electrodes. From the studies on the Raman spectra of polycrystalline CdSe films after annealing at 530°C where lines 2LO - and 3LO-phonons were observed, a conclusion is drawn on the quality of films. The reason for increasing the sensitivity of electrodes modified CdSe is an improved separation of electron-hole pairs in the space charge region (SCR) in contact with the electrolyte. Since the graphene structures are electron acceptors, so increasing the negative charge of the semiconductor surface in contact CdSe/GO, this leads to an increase in the surface electric field of the SCR. As a result of reduced recombination losses in the SCR, moreover, the GO particles can interact with the surface active sites which are recombination centers, so neutralizing the action of these centers. Composite photoanodes of NT-TiO2/CdSe/GO provide the evolution of hydrogen on platinum cathode as well as the cathode materials based on the reduced graphene oxide modified with nanoparticles of Pt, and multi-walled carbon nanotubes. The results obtained show that the investigated photoelectrodes are promising for use in the electrochemical systems for solar energy conversion.