Electrospun Metal Organic Framework Incoraporated Fibro Us Membranes For Oxygen Evolution Reaction And Dye Adsorption And Photodegradation

In nowadays society,there are still many problems including the sustained energy consumption,wasted resources and polluted water,which are seriously affecting natural ecology and human health.So for Oxygen Evolution Reaction(OER)and treatment of water pollution,it’s necessary to find a material with low consumption and high efficiency.Now,the metal organic frameworks(MOF)are standing out in many materials,which have high porosity and surface area,and have orderly and stable structure,although the application is restricted by its powder form.In addition,the electrospinning technique is attracting great attention because it has been widely used to prepare continuous nanofibers and the method is simple and controllable.The application of electrospun fibers can be greatly expanded by loading with other functional materials.Therefore,in this project,electrospinning method was used to prepare fiber membranes incorporated with MOF.The materials obtained were used for OER,and adsorption and photodegradation of dyes.The main research contents and conclusions are as follows:1.Polypropylene nitrile(PAN)fiber membrane incorporated with ZIF-67 was prepared by electrospining.The structure of obtained ZIF-67@PAN fibers was uniform and controllable.By changing the amount of ZIF-67 being loaded,fiber membranes with different structures and morphologies were obtained.When the weight ratio of ZIF-67 and PAN was less than 1,the ZIF-67 was attached to the PAN fiber in the form of nanoparticles.When the weight ratio was greater than or equal to 1,the structure of fiber membranes was like the microparticles in spider web(MSW).At the same time,other MOF could also be used to prepare MOF@PAN fiber membranes with unique MSW structure.2.ZIF-67@PAN fiber membranes were calcinated to prepare Co-based OER catalysts.After being calcinated,the conductivity of the carbonized PAN nanofiber materials was improved,and the formed Co/Co3O4 active sites evenly distributed over the material.Both the specific surface area of the electrocatalytic material and the exposure of Co/Co3O4 active sites were greatly increased because of the unique MSW structure.The results showed that the special structure of cobalt-based OER electrocatalytic materials had excellent electrocatalytic properties and cycling stability under alkaline conditions.When the alkaline solution was 1.0 M KOH and the current density was 10 mA cm-2,the overpotential was only 260 mV for the electrode material with the MSW structure.The electrochemical performance was better than most reported cobalt-based OER catalysts.When we studied the cycling stability with an overvoltage of 260 mV,the current density could remain at 95.3%of the initial current density after 8 h of cycling,showing low overpotential and high cycling stability.3.ZIF-67@PAN fiber membranes prepared by electro spinning were applied for methyl blue adsorption and photodegradation.For the ZIF-67@PAN-2 fiber membrane,under the condition of neutral aqueous solution,the adsorption and degradation efficiency of 10 mg L-1 methyl blue could reach 92.5%.The membranes could be reused after alcohol desorption,and the efficiency was still above 90%after 5 cycles,indicating that ZIF-67@PAN-2 fiber membrane materials are efficient for the absorption and photo degradation of methyl blue,and the reusability is good.