title: Understanding the Role of Dynamic Wettability for Condensate Microdrop Self-Propelling Based on Designed Superhydrophobic TiO2Nanostructures.
abstract: The ability to release the adhered drops on superhydrophobic surfaces is very important for self-cleaning, antifrosting/icing, microfluidic device, and heat transfer applications. In this paper, three types of in situ electrochemical anodizing TiO2nanostructure films are rationally designed and fabricated on titanium substrates with special superwettability, viz., TiO2nanotube arrays, irregular TiO2nanotube arrays, and hierarchical TiO2particle arrays (HTPA), and their corresponding behavior in condensate microdrop self-propelling (CMDSP) is investigated. Compared to the flat titanium counterpart, all three types of rough TiO2samples demonstrate a uniform distribution of smaller microscale droplets. Among the treated surfaces, the HTPA possesses the highest condensate density, and more than 80% of the droplets possess a diameter below 10 μm. Theoretical analysis indicates that the feature is mainly due to the morphology and structure induced extremely low droplet adhesion on super-antiwetting TiO2hierarchical surfaces, where the excess surface energy released from the migration leads to the self-propelling of merged microdrop. This work offers a way to rationally construct CMDSP surfaces with excellent self-cleaning, antifrosting/icing ability, and enhanced condensation heat transfer efficiency.
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China.
authors.forename: Songnan
authors.initials: S
authors.lastname: Zhang
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China.
authors.forename: Jianying
authors.initials: J
authors.lastname: Huang
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
authors.forename: Yuxin
authors.initials: Y
authors.lastname: Tang
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China.
authors.forename: Shuhui
authors.initials: S
authors.lastname: Li
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China.
authors.forename: Mingzheng
authors.initials: M
authors.lastname: Ge
authors.affiliation: School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore, 639798, Singapore.
authors.forename: Zhong
authors.initials: Z
authors.lastname: Chen
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China.
authors.forename: Keqin
authors.initials: K
authors.lastname: Zhang
authors.affiliation: National Engineering Laboratory for Modern Silk, College of Textile and Clothing Engineering, Soochow University, Suzhou, 215123, P. R. China.
authors.forename: Yuekun
authors.initials: Y
authors.lastname: Lai
keywords: TiO2 nanostructures; adhesion; condensate microdrops; electrochemical anodization; superwettability