Preparation Of Co₃O₄Superhydrophobic Films With Micro/Nano Structure Through Liquid Method And Anti-icing Behavior Study

The icing, being a kind of extreme weather phenomena, brings anyinconvenience to people’s life and production, even a security threat，endangering lifeand damaging the equipment. Especially for the outdoor transmission lines, theserious icing will cause the transmission tower to incline even to collapse, as well asline-breaking. So far, the traditional deicing method for the transmission lines cannoteffectively prohibit the ice disaster. Superhydrophobic surfaces absorb the wideattention from the researchers due to its special hydrophobicity. Therefore we wish tofundamentally solve the difficult problem of the icing of the high-voltage transmissionlines based on it. In this paper, simple solvothermal/hydrothermal method was usedto prepare two types of the Co3O4thin films with different microstructure. Afterchemical modification, not only do the thin film surfaces have excellentsuperhydrophobic properties, also show the obvious effect of anti-icing. The maincontent of the research are as follows.(1) Using solvothermal method, we successfully prepared Co3O4superhydrophobic surface with spherical micro/nanostructure on the glass substrate,and studied the formation mechanism of surface microstructure. Moreover, we alsofurther analyzed the physical and chemical mechanisms of superhydrophobicproperties by Cassie-Baxter composite model and found that, actual solid-liquidcontact area between the droplets and solid surface was only6.1%. Meanwhile, westudied both the effect of self-cleaning from the superhydrophobic surfaces and thedynamic behavior of water droplets on this surfaces. In addition, we designed anexperimental scheme to test the anti-icing properties of the sample. Its result indicatesthat Co3O4superhydrophobic surfaces can effectively delay freeze time of the waterdroplets.(2) Likewise, using hydrothermal method, we successfully prepared Co3O4superhydrophobic surfaces with flake-flowers micro/nanostructure on the Al substrate.We investigated in detail the microstructure evolution of the surfaces and the reactionmechanism by the SEM, together with the thermogravimetric analysis of precursor.Moreover，we studied the variations of the superhydrophobic performance of differenttypes of surfaces at different reaction time, and applied silver mirror phenomenon andhigh pressure water column to test consistency and stability of superhydrophobic performance of Co3O4surfaces respectively. Finally, anti-icing performance of thesuperhydrophobic surfaces was tested inside refrigerator by changing time andtemperature. The related results show that, the surfaces still have superhydrophobicperformance after being rinsed and dried; compared with the ordinary Al surfaces,Co3O4superhydrophobic surfaces can effectively reduce the accumulation of ice andice adhesion force.(3) Superhydrophobic transmission lines were prepared by applying Co3O4superhydrophobic surfaces with flake-flowers micro/nanostructure, and its anti-icingperformance were tested by simulating natural environment. Within a certain time andin the same conditions, superhydrophobic transmission lines had obvious effect ofanti-icing in low temperature environment even under ultra-low temperatureconditions of-25.3C.