Dust and ice contamination is a serious problem for equipment and vehicles for air and space mission applications. Dust contamination gathers on photonic sensors inhibiting motion and data gathering. Photonic devices that require transparency to light for maximum efficiency, such as solar photovoltaic power systems, video cameras and optical or infrared detectors, can be seriously affected by dust accumulation. The lunar thermal and radiation environment also pose unique challenges because of its large temperature variations and its interaction with the local plasma environment and solar UV and X-rays induced photoemission of electrons. Superhydrophilic materials are composed of polar molecules and have been used to defog glass, enable oil spots to be swept away easily with water, as door mirrors for cars and coatings for buildings. Hydrophobic molecules tend to be non-polar and thus prefer other neutral molecules and nonpolar solvents. Hydrophobic molecules often cluster together. Hydrophobic surfaces contain materials that are difficult to wet with liquids, with superhyrophobic surfaces having contact angles in excess of 150° (the equilibrium angle of contact of a liquid on a rigid surface where liquid, solid and gas phases meet). This paper presents an overview of the fundamental forces (van der Waals) which allows certain contamination to adhere to critical photonic surfaces and the various passive coatings phenomenology (hydrophilic to hydrophobic) that is used to minimize this contamination.

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On the lunar surface there exists very localized and weak magnetic fields, leaving its surface essentially directly exposed to the impact of solar UV and X-rays as well as solar wind plasma and energetic particles. The lack of atmosphere results in a lunar environment charging positive in sunlight and negative in shadow regions resulting in potentials that can vary over orders of magnitude in response to changing solar illumination and plasma conditions. At the macroscale, contaminant adhesion due to van der Waals' forces are very small and can be easily perturbed by other external forces. However, at the nanoscale, van der Waals forces can be significant. Lunar regolith or dust contamination is a serious problem for equipment and vehicles for space mission applications. Dust contamination gathers on photonic sensors inhibiting motion and data gathering. In addition, devices that require transparency to light for maximum efficiency such as solar photovoltaic power systems, video cameras and optical or infrared detectors will suffer from the dust accumulation. The electrostatic charging of the lunar surface is caused by its interaction with the local plasma environment and solar UV and X-rays induced photoemission of electrons. The lunar thermal environment poses unique challenges to vehicle and sensor surfaces since it is characterized by large temperature variations, long hot and cold soak times, and reduced heat rejection capability due to the presence of the lunar regolith. Fundamental forces (van der Waals) that allow certain contamination to adhere to critical surfaces and methods are being tailored to make these surfaces suitable for this harsh environment.