Controllable Synthesis,performances Of Porous Nano Structures Nickel Oxide

As a significant p-type semiconductor with a wide band gap（E_g=3.6⁴.0 eV）,nickel oxide（NiO）has been the focus of considerable attention ascribing to its high chemical and thermal stability,and environmental benignity,which is employed in catalysis,lithium-ion batteries,supercapacitors,gas sensors and adsorbents.In this paper,different morphologies of nickel oxide have been prepared by microwave-assisted chemical and hydrothermal method without surfactant;and leaf-like CuO-NiO was fabricated through microwave method,its performance has improved significantly.The samples were analyzed by X-ray diffractometer（XRD）,field emission electron scanning microscopy（FESEM）,transmission electron microscopy（TEM）.The main research as follows :1.Well dispersed hierarchical NiO architectures were successfully achieved via a green microwave-assisted aqueous chemical reaction followed by a calcination process.The as-prepared products were characterized by XRD,FESEM,TEM and N₂ adsorption/desorption isotherms.The results indicated that the three-dimensional（3D）flower-like microspheres with 400-600 nm in diameter are assembled by the pure cubic NiO nanosheets with the thickness of about 10 nm.It should be noted that the interconnecting ultrathin nanosheets have intercrystal mesoporosity and the inhomogeneous multimodal mesopores are ranging from 2.3 to 30.4 nm.A formation mechanism for NiO architectures was simply proposed.In addition,for dye removal in water,the as-obtained NiO as adsorbent exhibited a fast and high adsorption behavior for Congo red（CR）,the stability and rengeneration ability,suggesting a promising application in water treatment.2.On the basis of the flower-like NiO by changing the amount of urea,the homogeneous,fluffy sphere-like NiO was successfully obtained via microwave assisted aqueous chemical method with urea 20 mmol.The as-synthesized products were characterized by XRD,FESEM.And the spheres with about 800 nm in diameter are assembled by particles.The as-producted diaplays adsorption performance for congo red,and the capacity is estimated to be 142.25mg·g^-1.3.Without organic template agent,The ultrathin 2D patellate NiO were synthesized on a large scale by a mild hydrothermal route.The crystal structure and morphology of as-obtained products were investigated by XRD,FESEM,TWM.The results indicated that the nanosheets with the size of 1.8-2.5μm,and the thickness of 10-20 nm.The patellate NiO exhibited the better performance for the removal of Congo red（CR）from aqueous solution.The adsorption capacity for removal of congo red was 205.76mg·g^-1.Moreover,NiO architectures can be recycled by a simple facile process,which could retain the high removal efficiency in three successive cycles.This study suggests that porous patellate NiO could be explored as a new adsorbent with high efficiency and recyclability for removing organic dye pollutants from aqueous solution.4.The leaf-like CuO-NiO was fabricated by microwave-assisted aqueous chemical route,meanwhile,leaf-like CuO and NiO particles also obtained.The as-synthesized products were characterized by XRD,FESEM.C learly observed that NiO particles dispersed uniformly on the CuO blade from the FESEM.The electrochemical performance of products was studied via measurement cycle volt-ampere curve and constant current charge and discharge curves at different sweep speed and current density.The results indicated that the performance of composite was better than pure substance.They could be the optimized nanomaterials for super capacitors.