| Metal corrosion has caused a lot of economic losses and security risks to the society,so it is of great social and economic significance to study metal protection.The traditional cathodic protection anti-corrosion method can consume extra anode material or external electric energy,which caused huge material cost and economic pressure to enterprises.Triboelectric nanogenerator(TENG)is a new energy conversion device,which can transform mechanical energy into electric energy spontaneously by the coupling effect of triboelectrification and electrostatic induction.The electric energy generated by TENG can be used in metal cathodic protection to avoid or slow down the occurrence of metal corrosion.Compared with the traditional cathodic protection,the cathodic protection system supplied by TENG has the advantage of self-powered and intelligence.The anti-corrosion effect of metal is positively correlated with the output performance of TENG,and the output performance ultimately depends on the triboelectric effect of the material.Therefore,it has scientific research value and practical significance to optimize the triboelectric material for the development of self-powered anticorrosion system.In this thesis,polyvinyl chloride(PVC),which has the advantages of low cost,facile film preparation and excellent triboelectric effect,is used as triboelectric material,and a variety of TENGs based on PVC composite material were fabrication by optimizing triboelectric materials.The electronegativity and charge storage capability of the material were enhanced by introducing strong electronegativity and high dielectric properties respectively,and the output performance of device was improved;the output performance and durability of the device was improved simultaneously by introducing functional agent;In order to solve poor stability of particle doped polymer suspensions,the agent was introduced to improve both the stability of suspensions and the performance of devices.In addition,the electric energy generated by the device with optimized performance was used for metal cathodic protection to realize the self-powered anti-corrosion of metal.The practical assumption of applying TENG in metal anti-corrosion was put forward and verified,which broadened the application idea of new energy conversion technology in the field of metal anti-corrosion.The main research contents and conclusions are as follows:1.Graphene oxide(GO)with strong electronegativity was synthesized by Hummers method,Go was introduced into PVC matrix to prepare PVC-GO composite film,PVC-GO composite film was used as negative triboelectric material to assemble TENGs.The results show that the addition of GO significantly improved the output performance of device.When the doping amount of GO was 7 wt%,the short circuit current reached 5.3 ?A,which enhanced by 2.8 times than pure PVC TENG.In addition,the device with improved performance was used as the external power supply of cathodic protection,and a self-powered anti-corrosion system was assembled.The immersion experiments of metal show that the self-powered anti-corrosion system effectively slowed down the corrosion of metal.In the electrochemical test,the open-circuit potential decreased by 310 m V and the corrosion potential negative shifted by 166 m V,which indicated that the metal connected to the TENG produced cathodic polarization.2.Potassium metaniobate(KN)nanoparticles with high dielectric properties were synthesized by hydrothermal method,KN was introduced into PVC matrix to prepare PVC-KN composite film,PVC-KN composite film was used as negative triboelectric material to assemble TENGs.The results show that the output performance of device was greatly improved due to the introduction of KN.When the doping amount of KN was 9 wt%,the short circuit current got the optimal value of 24?A,which improved by 3.3 times than pure PVC TENG.In addition,the PVC-KN TENG was used as the external power supply of cathodic protection,and a self-powered anti-corrosion system was assembled.In the electrochemical test,the open-circuit potential decreased by 495 m V and the corrosion potential negative shifted by 476 m V.The immersion experiments and electrochemical tests showed that the TENG provided enough electrons to the metal for slowing down the corrosion of the metal.3.Stearic acid(SA),as a functional agent,was introduced into PVC matrix to prepare PVC-SA composite film,PVC-SA composite film was used as negative triboelectric material to assemble TENGs.The results show that the introduction of SA greatly improved the output performance and durability of device.When the doping amount of SA was 5 wt%,the short circuit current enhanced by 3.1 times than pure PVC TENG.The friction coefficient of PVC film reduced from 0.434 to 0.152,and the wear rate reduced by 82%,PVC-SA TENG has excellent durability compared with pure PVC TENG.In addition,the PVC-SA TENG was used as the external power supply of cathodic protection,and a self-powered anti-corrosion system was assembled.In the electrochemical test,the open-circuit potential decreased by 470 m V and the corrosion potential negative shifted by 437 m V.The effectiveness of the self-powered anti-corrosion system was proved by the electrochemical tests and immersion experiments.4.Using KN as a dopant and SA as a functional agent to prepare PVC-SA-KN composite film,PVC-SA-KN composite film was used as negative triboelectric material to assemble the contact-separation mode and single electrode mode TENGs.The results show the KN with high dielectric property and SA with strong electronegativity synergistically improved the output performance of device.When the doping amount of SA and KN was 5 wt% and 11 wt% respectively,the short circuit current of device in contact-separation mode increased from 1.1 ?A to 17.2 ?A.The addition of SA improved the dispersion stability of KN nanoparticles in PVC solution.The introduction of SA reduced the friction coefficient and the wear rate of PVC-KN film,which provided a guarantee for long-life time TENG.In addition,PVC-SA-KN composite film with a length of 90 cm and a width of 30 cm was prepared,which was used as a negative triboelectric material to assemble a smart floor based on a single electrode mode TENG,the intelligent floor can convert the mechanical energy into electrical energy and sensitive to human movement.When the experimenter moved on the intelligent floor,it provided 8 ?A peak current.Using the electricity generated by the smart floor for electrochemical corrosion protection of metals,in the electrochemical test,the open-circuit potential decreased by 381 m V,and the corrosion potential negative shifted by 312 m V,the electrochemical tests and immersion experiments showed that the smart floor provided enough electrons to cause cathodic polarization of metals,forming an effective self-powered anti-corrosion system. |
PDF Full Text Request