Photoelectric Synergetic Responsive Slippery Surfaces Based on Tailored Anisotropic Films Generated by Interfacial Directional Freezing

Smart responsive slippery surfaces are highly desirable for their potential applications in many fields. Although slippery surfaces that respond to a single external stimulus are reported, challenges in fabricating synergetic responsive anisotropic slippery surfaces remain due to limitations in the preparation of the underlying anisotropic substrate. Here, photoelectric synergetic responsive slippery surfaces are fabricated based on anisotropic porous films that are tailored by using an interfacial directional freezing technique using a poly(3‐hexylthiophene‐2,5‐diyl)/[6,6]‐phenyl‐C61‐butyric acid methyl ester (P3HT/PCBM) binary system. The anisotropic surface structure of P3HT/PCBM films is facilely tailored by simply tuning the freezing speed, the P3HT/PCBM mass ratio, and the total concentration of solution. A detailed formation mechanism is proposed and elucidated. Moreover, anisotropic slippery surfaces demonstrate remarkable photoelectric synergetic behavior, which is used for the photoelectric synergetic control of droplet sliding and interfacial sentinel oxidative degradation. The in‐depth understanding of the formation mechanism of the anisotropic porous film may enable the interfacial directional freezing method to be extended to the design of other multifunctional anisotropic surfaces. This work will provide a theoretical basis for the design of new types of smart slippery surfaces, which are potentially useful in microfluidics, lab‐on‐chips, photoelectric displays, interfacial microreactors, and other related fields. Photoelectric synergetic responsive slippery surfaces are prepared using anisotropic films generated by an interfacial directional freezing technique using a binary system. The mechanism for fabricating the anisotropic porous film is discussed in detail. The photoelectric synergetic control of droplet sliding on a slippery surface is achieved, and the slippery surface can be used for interfacial sentinel oxidative degradation of organic contaminants.