Photoelectric properties of nanofibers of composites based on cobalt oxide with zinc

In this work, the photoelectric properties of Co3O4/Zn composites with different contents of zinc atoms in the range from 0 to 33 mole percent by cation (mol%) were studied. The composites were obtained by electrospinning and consisted of nanofibers 150–200 nm in diameter with a nanocrystalline structure. The possibility of increasing the dark conductivity and photoconductivity of Co3O4/Zn composites by adding zinc atoms to the structure has been demonstrated. It has been found that the kinetics of the rise and fall of photoconductivity when samples are illuminated with ultraviolet radiation can be approximated by the sum of two exponentials. This indicates the existence of two different processes that determine the recombination of nonequilibrium charge carriers in the material. It is shown that one of these processes can be associated with the adsorption and desorption of molecules on the surface of nanofibers. The ability to carry out adsorption and desorption due to illumination of Co3O4/Zn composites makes them promising for use in gas sensors.