title: Synergetic effects of Sr-doped CuBi2O4 catalyst with enhanced photoactivity under UVA- light irradiation.
abstract: Sr-doped CuBi2O4 micro-particles were successively synthesized via a solid-state technique and were analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and UV-vis diffuse reflectance spectroscopy (UV-vis-DRS) techniques. Results show that Sr-doped CuBi2O4 was crystallized with a spinel-type structure and tetragonal crystal system, and the band gap energy was about 1.35 eV. The as-prepared Sr-doped CuBi2O4 treated at 573 °C for 12 h exhibited the highest efficiency, as a result of 97.22 % of CR degradation within 220 min, which is approximately 31 times greater than CR photodegradation when catalyzed by CuBi2O4 (3.13 %) and about 2.3 times superior than that catalyzed by the untreated Sr-doped CuBi2O4 sample (42.08 %). Pseudo-first-order kinetic model gave the best fit, with highest correlation coefficients (R (2) = 0.94-0.97). The Sr-doping and extending reaction time up to 12 h could be effective in producing Sr-doped CuBi2O4 materials that delay electron-hole recombination, thereby increasing the lifetime of the electron electron-hole separation and support the charge carrier transfer to the catalyst surface. On the basis of the calculated energy band positions, superoxide radical anions (O2 (•-)) were the main oxidative species responsible for the photocatalytic degradation of CR dye solution.
authors.affiliation: Dr. Moulay Tahar University, Saida, Algeria. elaziouti_a@yahoo.com.
authors.forename: A
authors.initials: A
authors.lastname: Elaziouti
authors.affiliation: Dr. Moulay Tahar University, Saida, Algeria.
authors.forename: N
authors.initials: N
authors.lastname: Laouedj
authors.affiliation: LCMIA Laboratory of Inorganic Materials Chemistry and Application, University of the Science and the Technology of Oran (USTO M.B), BP 1505, El M'naouar, 31000, Oran, Algeria.
authors.forename: A
authors.initials: A
authors.lastname: Bekka
mesh_terms: D001729:Bismuth / Q000737:chemistry; D002384:Catalysis; D007700:Kinetics; D008027:Light; D008855:Microscopy, Electron, Scanning; D055668:Photochemical Processes; D010782:Photolysis; D013324:Strontium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014961:X-Ray Diffraction
chemical_list: C033301:bismuth oxide; D001729:Bismuth; D013324:Strontium
keywords: Band theory; Congo red; Photocatalytic efficiency; Sr-doped CuBi2O4; Synergy effect