Luminescent properties of spark eroded ZnO nanopowder

ZnO nanomaterial has many practical applications in particular in microelectronics. ZnO nanopowder was obtained by spark erosion method in water. According to the X-Ray diffraction (XRD), scanning electron microscopy (SEM) and transmitting electron microscopy (TEM) data powder consists of agglomerates of ZnO particles with average size of 25 nm. Photoluminescent study shows that spark eroded ZnO nanopowder has a wide photoluminescence (PL) peak between 350 and 700 nm. It consists of minimum 7 lines which can be attributed to the donor-acceptor recombination, impurities and defects such as zinc and oxygen vacancies, interstitial Zn and surface dislocations. Therefore, the spark eroded ZnO nanopowder demonstrates a self-activated photoluminescence.