Based On Black TiO₂NTAs Composite Photoelectrode Preparation And Photocatalytic Degradation Of Organic Wastewater

Advanced oxidation processes（AOPs）including photocatalysis,photocatalysis and Fenton oxidation,which rely on the generation of hydroxyl radicals to purify the environment.At present,it can be seen that photoelectric catalysis（PEC）technology is usually applied in many different fields of environmental pollution treatment,especially in the degradation of non-biodegradable organic pollution,which can effectively decompose organic compounds in aqueous solutions.In the process of degradation,photoelectrodes play an important role in the degradation efficiency of pollutants.TiO₂NTAs is one of the most widely used photocatalytic materials due to its non-toxicity,good optical properties,large specific surface area,corrosion resistance and low cost.Compared with other TiO₂ structures,the nanotubes have an ideal one-dimensional geometry and can effectively transfer charge.In addition,TiO₂NTAs formed on Ti substrate by anodic oxidation is not only easy to be recovered,but also can be used as an electrode.When a certain bias voltage is applied to the TiO₂NTAs electrode,electrons are driven to the sample surface to improve the photoelectric catalytic efficiency of the photoelectrode.Therefore,a series of researches were carried out with the goal of improving the catalytic activity of TiO₂NTAs photoelectrode.The main research contents are as follows:Under the reduction voltage of-2V,Black-TiO₂NTAs was prepared by cathodic electric reduction.In addition,a series of tests showed that Black-TiO₂NTAs performed better than ordinary anatase TiO₂NTAs.Using Black-TiO₂NTs as the substrate,Ni/Ni O and ZIF-9（porous matrix material）particles were successively loaded on Black-TiO₂NTAs by pulse electrodeposition technique and microwave reaction method.The composite Ni-ZIF-9-Black-TiO₂NTAsphotoelectrode was successfully prepared and the influence of Ni and ZIF-9 particles and the photoelectric property of the electrode were studied.Through scanning electron microscope（SEM）,X-ray diffraction（XRD）,energy dispersive X-ray spectroscopy（EDX）,X-ray photoelectron spectroscopy（XPS）,UV-vis diffuse reflection spectroscopy（UV）and nitrogen isothermal adsorption/desorption characterization methods of modified electrode surface morphology,phase structure,element composition and valence state of physical and chemical properties of the thorough analysis.In addition,tests such as Linear voltammetry（LSV）,photocurrent,Motschottky curve（MS）and electrochemical impedance spectroscopy（EIS）were performed to investigate the photochemical properties of the modified photoelectrode.The experimental results show that the modified Ni-ZIF-9-Black-TiO₂NTAs has a larger specific surface area,narrower band gap width,higher photocurrent and smaller electron transfer resistance than Black TiO₂NTAs and Ni-Black-TiO₂NTAs.Methyl orange（MO）was selected to simulate organic wastewater.Through exploring a series of experiments of factors affecting degradation efficiency,the experimental conditions of degradation were determined:concentration of 5mg/L,bias potential of 0.6V.The modified Ni-ZIF-9-Black-TiO₂NTAs photoelectrode and copper sheet were used as anode and cathode,respectively.Under visible light irradiation and0.6V voltage applieded,the MO removal rate and mineralization efficiency reached94.01%and 74.1%after 180 min of degradation,which showing better photoelectric catalytic performance.In addition,the possible mechanism of photoelectrocatalytic degradation（PEC）of MO was proposed based on all the above test results.In conclusion,we concluded that the new Ni-ZIF-9-Black-TiO₂NTAs photoelectrode had excellent catalytic performance.CuS-ZIF-8-Black-TiO₂NTAs photoelectrode was successfully prepared by hydrothermal and in situ growth methods.SEM,XRD and XPS results show that flower-shaped CuS hollow nanospheres and ZIF-8 nanoparticles were successfully loaded on the surface of Black TiO₂NTAs.In addition,the photoelectrochemical properties of the photoelectrodes were studied through a series of experiments.In addition,under visible light irradiation,CuS-ZIF-8-Black-TiO₂NTAs photoelectrode has excellent photoelectric catalytic performance.The influence of bias voltage and Rhodamine B（Rh B）initial concentration on degradation rate were investigated.The degradation conditions were determined:concentration was 5mg/L,bias was 0.8V.The degradation efficiency and mineralization efficiency of CuS-ZIF-8-Black-TiO₂NTAs were 98.1%and 82%,respectively.Finally,a possible degradation pathway of Rh B was proposed based on all the test results.This study shows that the new CuS-ZIF-8-Black-TiO₂NTAs photoelectrode have a potential application prospect in environmental purification.Figure 26 Table 8 Reference 82...