Surface coating and method for reducing the contamination tendency of the surface of an object
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing surface coatings for photovoltaic modules and other transparent or reflective surfaces fail to effectively reduce soiling under extreme outdoor conditions, such as desert regions, where water scarcity and harsh weather limit their self-cleaning effectiveness.
Innovation Solution
A nanoporous surface coating with a hydrophobic exterior and a hydrophilic interior water storage layer, capable of absorbing and storing water through capillary forces, preventing surface wetting and reducing adhesion of dust particles by vertically transporting moisture and using thermal management to evaporate stored water.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional surface coatings with micro- or nanoscopic roughness are used to reduce soiling, then adhesion of dust particles is reduced, but the coatings fail to maintain effectiveness under extreme outdoor conditions such as water scarcity and harsh weather
Solution Approach 1:
The coating is designed with spatially varying properties: the upper region contains hydrophobic components that repel water and prevent wetting, while the lower region contains hydrophilic components that absorb and store water through capillary forces in nanopores. This local differentiation allows the coating to maintain anti-soiling properties by keeping the surface dry while having internal water storage capability for self-cleaning functions.
Solution Approach 2:
The coating combines multiple materials with complementary properties: hydrophobic materials (such as fluorinated compounds or wax) are integrated with hydrophilic materials (such as silica gel or alumina) containing nanopores. This composite structure enables simultaneous water repulsion at the surface and water absorption in the interior, creating a functional gradient that enhances reliability under varying environmental conditions.
2Object-affected harmful factors
If water is used for manual or automated cleaning to remove dust particles, then soiling is reduced, but water consumption increases which is problematic in water-scarce regions
Solution Approach 1:
The coating enables self-cleaning functionality by incorporating water storage capability within its structure. Condensed moisture or dew is automatically absorbed and stored in the hydrophilic nanoporous region, then utilized to detach and remove dust particles from the hydrophobic upper surface without requiring external water application or manual cleaning intervention.
Solution Approach 2:
The coating converts condensed moisture, which could potentially cause cementation of dust particles and worsen soiling, into a beneficial cleaning agent. The hydrophilic interior captures condensed water and uses it to lift and remove particles from the surface, transforming what would be a harmful effect into a self-cleaning mechanism that reduces water consumption.
3Object-affected harmful factors
If the surface is made hydrophobic to prevent water adhesion and reduce soiling, then dust particle adhesion is reduced, but condensed moisture cannot be utilized for self-cleaning
Solution Approach 1:
The coating is designed with spatially varying properties: the upper region contains hydrophobic components that repel water and prevent wetting, while the lower region contains hydrophilic components that absorb and store water through capillary forces in nanopores. This local differentiation allows the coating to maintain anti-soiling properties by keeping the surface dry while having internal water storage capability for self-cleaning functions.
Solution Approach 2:
The solution moves the water storage function from the surface dimension to the subsurface dimension. By creating a vertical gradient where hydrophobic properties dominate at the surface and hydrophilic properties dominate in the interior, the coating prevents water adhesion at the surface level while enabling water absorption and storage at deeper levels, thus resolving the contradiction between water repulsion and water utilization.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The coating maintains a dry surface over extended periods, reducing soiling and enhancing natural cleaning mechanisms like wind, while maintaining optical transparency and stability, even in extreme environments.
Implementation Method 1
a hydrophobic surface and a hydrophilic interior, acting as a water storage layer
Implementation Method 2
capable of absorbing and storing water through capillary forces
Implementation Method 3
acting as a water storage layer with a water storage capacity
Implementation Method 4
vertically transporting moisture
Implementation Method 5
using thermal management to evaporate stored water
Data Source
Figure 1A~1D
Figure 1E~1F
Figure 2A~2C
AI summary
The present invention relates to a surface coating and a method for reducing the susceptibility to soiling of an object surface, in particular the surface of photovoltaic modules. The surface coating is formed by a nanoporous layer or layer sequence (2) which has a hydrophobic surface and a hydrophilic interior. The surface coating can reduce the susceptibility to soiling of an object surface even under extreme environmental conditions, such as those occurring in desert regions.