Synthesis And Properties Of Metal Oxide Nanocomposites

Metal oxides, such as TiO2, SnO2and Cu2O,’have a wide range of applications in battery, catalyst and sensors, and other fields, due to their unique physical and chemical properties. The nanocomposites which based on these metal oxides havestrong vitality in the future field of material science because they possess excellentcomprehensive performance and can be easily designed. At the same time, nanocomposites also become an important direction of the development of the new material. This article revolves around the preparation and property research of different metal oxide nanocomposites. Particularly, their liquid phase preparation process and photocatalytic degradation of pollutants and the electrochemical detection of glucose performance of the prepared materials are studied in this paper. The main research content includes the following three aspects:1. Microwave-assisted deposition of metal sulfide/oxide nanocrystals onto a3D hierarchical flower-like TiO2nanostructure with improved photocatalytic activityIn the present chapter,3D hierarchical fower-like TiO2nanostructures were first prepared via a facile one-pot solvothermal approach followed by an annealing treatment, and then acted as the supporting materials in the following microwave-assisted reaction process. After absorbingmetal ions on the surface of TiO2nanoflowers in the presence of thioacetamide (TAA) or hexamethylenetetramine (HMT), the mixture was placed in a microwave refluxing system and irradiated at300W for30min to obtain TiO2-based metal sulfide/oxide hetero-nanostructures. We choose the as-prepared TiO2-CdS hetero-nanostructure as an example, which exhibits obviously enhanced photocatalytic activity for the photodegradation of methyl orange (MO) compared with TiO2nanoflowers, P25and pure CdS under visible-light irradiation. Therefore, the TiO2-MS/MO hetero-nanostructure developed in this work may be a promising potential material for pollutant treatment.2. A controllable hydrothermal-assisted self-hydrolysis of SnS2nanoplates route to fabricate SnS2/SnO2heterostructured nanoplates with enhanced visible-light-driven photocatalytic reduction of Cr(VI)A novel and facile hydrothermal-assisted self-hydrolysis route has been first proposed for the controllable preparation of SnS2/SnO2heterostructured nanoplates (HNPs), which only use the pregrown SnS2nanoplates as precursors without employing any additional surfactant and self-hydrolysis of SnS2occurs in the pre-sence of citric acid at180℃for different time. Very interestingly, the size, morphology and content of SnO2in the SnS2/SnO2HNPs can be conveniently tuned by just varying the reaction time in the hydrolytic process. Benefiting from the unique structural features, the as-prepared SnS2/SnO2HNPs exhibit significantly higher visible-light-driven photocatalytic activity in the reduction of aqueous Cr(VI). Furthermore, the mechanisms of the optimal SnO2content to reach the maximum photocatalytic activity in the SnS2/SnO2HNPs are proposed and discussed.3. Facile Growth of Cu2O Nanowires on Reduced Graphene Sheets with High Nonenzymatic Electrocatalytic Activity Toward GlucoseA simple solvothermal approach for the synthesis of cuprous oxide (Cu2O) nanowires on reduced graphene oxide (rGO) is demonstrated. The formation of well-dispersed Cu2O nanowires onto rGO were accomplished by using ethylene glycol(EG) as solvent and reductant, cupric acetate and rGO as initiating materials and soldium acetate as precipitator. The process carried out at120℃for6h. The diameter of the Cu2O nanowires anchored on the RGO sheets are about5nm. The proposed sensors exhibit linear behavior in the concentration range from10u M to0.1mM, with a high gradient of80.17μA·mM-1. The resulting rGO-Cu2O nanowires composites shows good response to glucose and manifests good selectivity and sensibility compared to pure Cu2O nanowires. More importantly, the nanohybrids modified electrode show high resistance against other normally co-existing electroactive species such as uric acid, dopamine, ascorbic acid. Thus, rGO-Cu2O nanowires nanocomposites are promising electrode materials for the determination of glucose.