Super-hydrophobic coatings based on non-solvent induced phase separation during electro-spraying

Jiefeng Gao, Xuewu Huang, Ling Wang, Nan Zheng, Wan Li, Huaiguo Xue, Robert K.Y. Li, Yiu Wing Mai

Research output: Journal article publicationJournal articleAcademic researchpeer-review

54 Citations (Scopus)


Hypothesis The polymer solution concentration determines whether electrospinning or electro-spraying occurs, while the addition of the non-solvent into the polymer solution strongly influences the surface morphology of the obtained products. Both smooth and porous surfaces of the electro-sprayed microspheres can be harvested by choosing different non-solvent and its amount as well as incorporating polymeric additives. Experiments The influences of the solution concentration, weight ratio between the non-solvent and the copolymer, and the polymeric additives on the surface morphology and the wettability of the electro-sprayed products were systematically studied. Findings Surface pores and/or asperities on the microsphere surface were mainly caused by the non-solvent induced phase separation (NIPS) and subsequent evaporation of the non-solvent during electro-spraying. With increasing polymer solution concentration, the microsphere was gradually changed to the bead-on-string geometry and finally to a nanofiber form, leading to a sustained decrease of the contact angle (CA). It was found that the substrate coatings derived from the microspheres possessing hierarchical surface pores or dense asperities had high surface roughness and super-hydrophobicity with CAs larger than 150° while sliding angles smaller than 10°; but coatings composed of microspheres with smooth surfaces gave relatively low CAs.

Original languageEnglish
Pages (from-to)603-612
Number of pages10
JournalJournal of Colloid and Interface Science
Publication statusPublished - 15 Nov 2017
Externally publishedYes


  • Electro-spraying
  • Microspheres
  • Porous
  • Super-hydrophobic

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Biomaterials
  • Surfaces, Coatings and Films
  • Colloid and Surface Chemistry


Dive into the research topics of 'Super-hydrophobic coatings based on non-solvent induced phase separation during electro-spraying'. Together they form a unique fingerprint.

Cite this