Solar active ZnO-Eu2O3 for energy and environmental applications

ZnO-Eu2O3 nanocomposite was fabricated by a simple hydrothermal route. This material forms a potential class of photocatalysts in which the increased absorption behaviour in ZnO-Eu2O3 is expected to couple with the existing characteristics of Eu2O3 and ZnO materials. ZnO-Eu2O3 was characterized using surface analytical (SEM, EDS, HR-TEM, AFM, XRD) and spectroscopic techniques (XPS, DRS,PL). From the XRD patterns, formation of well-crystallized cubic Eu2O3 and hexagonal wurtzite phase of ZnO were inferred. Presence of nanoflake like structure with hexagonal ZnO and cubical Eu2O3 is shown by SEM pictures. ZnO-Eu2O3 possesses higher UV and visible absorption than Eu2O3 and ZnO. ZnO-Eu2O3 produces larger methanol oxidation current indicating its anodic catalytic efficiency in direct methanol fuel cells (DMFCs). This reveals higher electrocatalytic activity of ZnO-Eu2O3 than ZnO. It is observed that at -1.6 V, cathodic current density (ipc) of ZnO-Eu2O3 (-103.17 mA cm(-2)) for Hydrogen evolution reaction (HER) is more than five times of ZnO (-18.19 mA cm(-2)) and the hydrogen evolved with ZnO-Eu2O3 is 15.6 mL, which is higher than that of ZnO (6.8 mL). This indicates the superior catalytic property of ZnO-Eu2O3 in water splitting. This catalyst exhibited higher catalytic activity of 99.2% in the photodegradation of Rhodamine B (Rh-B) with natural sunlight in 75 min under neutral pH, whereas Eu2O3 and ZnO produced 60 and 82% degradations in the same time. Degradation quantum efficiency by ZnO-Eu2O3 is larger than ZnO and Eu2O3. ZnO-Eu2O3 was stable and reusable. The multifunctionality of this catalyst makes it suitable for energy and environmental applications.