Hydrophilic antifogging surfaces: Principle, fabrication, and progress

Transparent materials such as eyeglasses, car windshields, and optical instruments play an important role in our daily lives due to their excellent transparency. However, water vapor frequently condenses into droplets on solid surfaces due to temperature variations and other factors (e.g., high humidity), leading to light scattering and decreasing the transparency of transparent materials. Therefore, the investigation of novel antifogging mechanisms and the advancement of effective antifogging technologies have emerged as popular subjects in both fundamental theory research and practical research areas. There are two main approaches to preventing fogging. The first one is to change environmental factors such as temperature, humidity, and air flow, while the other one is to adjust the wettability of solid surfaces. The latter offers a significant advantage over the former due to its ability to achieve spontaneous antifogging properties, leading to widespread attention across various fields. This Review summarizes hydrophilic antifogging mechanisms and the development of three surface types: organic, inorganic, and organic–inorganic hybrid antifogging surfaces. It highlights advancements in multifunctional integration, including anti-reflection, self-cleaning, self-healing, and anti-bacterial properties, which broaden application scopes by enhancing surface functionalities.