Photoluminescence and structure study in mixture of ZnO and carbon nanoparticles during mechanical activation

The photoluminescence and X ray diffraction of the mixture of ZnO + 1.0% C nanocrystals (NCs) have been studied before and after intensive mechanical processing (MP) with the aim to identify the nature of emission bands and radiative defects. The study reflects the diversity of physical processes occurring during MP: the destruction of primary ZnO NC aggregates, crushing individual ZnO NCs from the size of 250 nm down to 14 nm, the interaction of carbon atoms with oxygen in a treatment chamber and with the surface of ZnO nanoparticles etc. The new PL band peaked at 2.84-2.95 eV has been revealed in PL spectra after 9 min of MP. The origin of this emission in ZnO has not been conclusively established. The new PL band peaked at 2.84-2.95 eV has been studded and its nature is discussed.