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Rational design and controlled synthesis of semiconducting metal oxide materials with nanoscopic structures and unique properties have been an interesting area. In this work, a large scale of tin dioxide nanowires (SnO2 NWs) on Ti foils are synthesized through a simple hydrothermal method at 180 °C. The results show that SnO2 NWs have a single crystalline structure with an average diameter of 40 nm and a large surface area. The SnO2 NWs exhibit excellent performance in both adsorption and degradation of methylene blue due to the high surface area and photocatalytic property. The photochemical sensing of glucose by the as-obtained material presents a low detection limit and high sensitivity, ranging from 0.01 to 0.05 mM. [ABSTRACT FROM AUTHOR]

LaFeO 3 /MgFe 2 O 4 heterojunctions were prepared via the sol-gel route to enhance solar-light induced photo-persulfate degradation of tetracycline hydrochloride (TCH). LaFeO 3 /MgFe 2 O 4 exhibited the better removal efficiency of TCH in comparison to LaFeO 3 and MgFe 2 O 4. The photo-persulfate activity of LaFeO 3 /MgFe 2 O 4 was intensively affected by LaFeO 3 content, pH, and inorganic salts. Under the optimal conditions, 2-LaFeO 3 /MgFe 2 O 4 with a nominal LaFeO 3 content of 10 wt % presented the removal efficiency of 97.01 %, while declined to 85.40 % after ninth-cycle test. The lattice defects formed in LaFeO 3 and MgFe 2 O 4 acted as the active sites for TCH adsorption and photon capture. The oxygen-defected tight interface between LaFeO 3 and MgFe 2 O 4 was favorable for the separation and migration of photo-induce e-/h+ pairs, boosting solar-light response for photo-persulfate activity of LaFeO 3 /MgFe 2 O 4. However, the long-term photo-corrosion inevitably induced to the change in valance states of surface compositions, weakening the photo-persulfate performance in TCH elimination. [Display omitted] • LaFeO 3 /MgFe 2 O 4 hybrids were prepared via the sol-gel approach. • LaFeO 3 /MgFe 2 O 4 had the strong solar-light photo-persulfate activity for TCH degradation. • The tight interface favored the transfer and migration of photo-induced e-/h+ pairs. • Photo-induced radicals and Fe2+/Fe3+ couples promoted the persulfate oxidation. [ABSTRACT FROM AUTHOR]

Metal oxides-based heterojunction fabrication is a promising strategy to eliminate antibiotics from wastewater via adsorption-photocatalysis. ZnLa x Bi 2−x O 4 hybrids with various La/Bi molar ratios were fabricated for enhancing the adsorption-photocatalytic elimination of tetracycline hydrochloride (TCH). Oxygen-defected ZnLa x Bi 2−x O 4 composites provided the sufficient sites for photon capture and pollutants adsorption. In addition, the tight p-n-p type interface among oxygen-defected La 2 O 3 , ZnO, and spinel ZnBi 2 O 4 favored the rapid transfer and migration of photo-excited e-/h+ pairs, enlarging the visible light utilization. Hence, ZnLa x Bi 2−x O 4 samples had the better adsorption-photocatalytic activity than ZnLa 2 O 4 and ZnBi 2 O 4 for TCH removal. Langmuir and second-order models well described the adsorption isotherms and kinetics of ZnLa x Bi 2−x O 4 samples, respectively. The adsorption capacity of optimal ZnLa 1.75 Bi 0.25 O 4 with a La/Bi molar ratio of 7:1 was 406.85 mg g−1, and its removal efficiency of 210 mg L−1 TCH solution was 98.04 % within 150 min. The change in valence states of surface compositions induced to the declined removal efficiency of ZnLa 1.75 Bi 0.25 O 4 to 91.95 % after five cycle times. [Display omitted] • ZnLa x Bi 2−x O 4 heterojunctions had the excellent adsorption-photocatalytic activities. • The adsorption capacity of optimal of ZnLa 1.75 Bi 0.25 O 4 was 406.85 mg g−1. • The removal efficiency of 210 mg L−1 TCH solution over ZnLa 1.75 Bi 0.25 O 4 was 98.05 %. • Langmuir and second-order models well fitted with the adsorption behaviors of ZnLa x Bi 2−x O 4. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, core–shell CoFe2O4–carbon composite nanoparticles (CCNPs) were synthesized via the thermolysis of a heterometallic trinuclear complex [CoFe2O(CH3COO)6(H2O)3·2H2O] in a one-end closed horizontal tube furnace. The products were characterized by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDX), Raman spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). XRD and EDX analyses revealed a pure ferrite phase with high crystallinity and the composition elements of C, Co, Fe and O with the rate of Co, Fe, and O to the CoFe2O4 theoretical value. Raman spectroscopy indicates amorphous carbon in the products. Morphological investigation by SEM and TEM showed the CCNPs have an average particle size of 50nm coated with carbon on the surface. The reaction temperatures were evaluated and magnetic measurement shows that the formed CCNPs have smaller saturation magnetization than bulk cobalt ferrite at room temperature. [Copyright &y& Elsevier]