Cost-effective ZnO–Eu3+ films with efficient energy transfer between host and dopant

The present work focuses on the deposition of Europium (Eu3+) incorporated zinc oxide (ZnO) film by a cost effective chemical solution deposition method. ZnO film with varying concentration of Eu3+ ions (2, 3 and 4 atomic percent) were deposited and characterized using different techniques like X-ray diffractogram (XRD), scanning electron microscopy. XRD studies revealed that highly c-axis oriented ZnO films without showing any segregation of europium oxide were obtained at 650 °C. The optical properties were determined using UV–visible spectrophotometry and photoluminescence measurements. UB-visible spectroscopy revealed that Eu3+ doping shifted optical band gap with increase in transparency of the films. The Eu3+ doped film showed intense emission at 614 nm which was attributed to the defect emission from ZnO that gets trapped by Eu3+ ions ultimately leading to 7F2 to 5D0 transition in Eu3+.