Image analysis of PDMS/ZnO nanocomposite surfaces for optimized superhydrophobic and self-cleaning surface design

•PDMS/ZnO nanocomposite surfaces are produced by spraying nanoparticles (NPs) on PDMS.•ZnO NPs surface distribution and agglomeration parameters are obtained by image analysis.•NPs hydrophobization promotes superhydrophobic and self-cleaning PDMS surfaces.•Surface parameters were correlated to roughness, morphology, superhydrophobicity and self-cleaning properties.•Higher fraction of agglomerates and lower agglomerate radius and interdistance is observed for hydrophobic NPs.