Fouling on glass surfaces reduces
the solar panel efficiency
and
increases water consumption for cleaning. Superhydrophobic coatings
on glass enable self-cleaning by allowing water droplets to carry
away dirt particles. Observing the interaction between charged particles
and surfaces provides insights into effective cleaning. Using a high-speed
camera and a long-distance objective, we analyzed the in situ deposition of variously functionalized and charged silica dust microparticles
on chemically treated glass. The ambient charges for the control,
hydrophobic, and positively charged particles were approximately −0.5,
−0.13, and +0.5 nC, respectively. We found that a positively
charged particle of 2.3 ± 1.2 μm diameter adhered to hydroxylated
glass in ∼0.054 s, compared to 0.40 and 0.45 s for quaternary
ammonium- and fluorosilane-functionalized hydrophobic glass. Experiments
suggest that quaternary ammonium-functionalized glass surfaces are
about 77.8% more resistant to soiling than bare surfaces.