Preparation And Application Of Bubble-driven Micro Motors Based On Biological Morphology

Due to potential environmental and biochemical applications,chemically driven nano/micron size motors have received increasing attention.Micromotors can increase the microscopic mixing of substances in solution due to their autonomous motion and their synergy.In the face of increasingly serious water pollution problems,adsorption and photocatalysis are widely used in wastewater treatment,but conventional photocatalytic adsorption methods can only statically absorb photocatalytic degradation of pollutants.Separation analysis technology that mimics the specific recognition of template molecules by the mechanism of antigen-antibody reaction is a technique that extracts template molecules statically.We combined photocatalytic adsorption,molecular imprinting,and micromotors to increase photocatalytic and adsorption efficiency.The main research content and conclusions of this paper:1.Based on absorbent cotton with natural asymmetrical morphology,porous activated carbon was prepared by chemical activation,and Mn₃O₄/ZnO/ACF micromotor that retained the asymmetric morphology of absorbent cotton was prepared by microwave method and hydrothermal method.Mn₃O₄/ZnO/ACF micromotors were characterized and analyzed by XRD,SEM,TEM,BET,XPS.The results showed that a micromotor with a diameter of approximately 10?m based on the appearance of absorbent cotton was prepared.For the micromotor study,videos were captured by an optical microscope Microscope N-300M,coupled with a digital camera DC2000 digital camera using the TSview software to analyze the speeds of autonomous micromotors.The degradation of methylene blue by micromotors was studied.The effects of different hydrothermal temperatures on the degradation performance of micromotors were studied.The results showed that the degradation rate of methylene blue was highest when the sample prepared with the temperature of 160?.In addition,the movement speed and the movement efficiency of a micromotor driven by Mn₃O₄decomposing hydrogen peroxide in different concentrations of hydrogen peroxide solution were studied.When the concentration of hydrogen peroxide was increased from 3%to 7%,the moving speed of micromotors increased with the increase of hydrogen peroxide concentration,and its moving speed increased from 81.78±11.25?m s^-1 to 198.14±19.86?m s^-1.Finally,the degradation efficiency of methylene blue by the micromotor under static and moving conditions was compared.The degradation efficiency of the micromotor under motion was about twice as high as the degradation efficiency at rest.2.Based on the natural asymmetric tubular morphology of kapok,micromotor was made with MnO₂ loaded on the single end of kapok.A magnetically imprinted micromotor was prepared by hydrothermally loading aminated Fe₃O₄ on the surface of a micromotor and performing molecular imprinting using bovine hemoglobin as a template protein.The phase and morphology of the magnetic imprinted micromotor were characterized by XRD,SEM,TEM,and IR.The results showed that the molecular imprinting micromotor retained the natural asymmetrical morphology of kapok.Catalyzed decomposition of H₂O₂ by asymmetrically distributed MnO₂ generated bubbles that drived the movement of magnetically imprinted micromotors.We had studied the adsorption properties of bovine hemoglobin by a magnetic imprinting micromotor,the optimal imprinting conditions were obtained by changing the amount of functional monomer added:V_APTES=V_OTMS=60?L.The prepared magnetically imprinted micromotor achieved adsorption equilibrium at 0.6 h in a stationary state and had a maximum adsorption capacity of 35.72 mg g^-1 for bovine hemoglobin.Fitting the adsorption process showed that the adsorption process conformed to the pseudo-second-order kinetics model and the Langmiur model.The adsorption of bovine hemoglobin was a monolayer chemisorption in the surface layer of the micromotor.The movement of the micromotor was achieved by adding a small amount of H₂O₂ to the bovine hemoglobin solution,the adsorption rate of the bovine hemoglobin by the magnetic imprinted micromotor under motion was significantly increased.Due to the introduction of magnetic material,the magnetic imprinting micromotor can be recovered.The blotting protein could be eluted by NaOH solution and the magnetic analysis of the imprinted micromotor can be reused.