Hierarchical Ag nanostructures on Sn-doped indium oxide nano-branches: super-hydrophobic surface for surface-enhanced Raman scattering

Kyungchan Min; Kyoung Soon Choi; Wook Jin Jeon; Dong Kyu Lee; Sein Oh; Jouhahn Lee; Jae-Young Choi; Hak Ki Yu

doi:10.1039/c8ra01510d

Hierarchical Ag nanostructures on Sn-doped indium oxide nano-branches: super-hydrophobic surface for surface-enhanced Raman scattering

RSC Adv. 2018 Apr 6;8(23):12927-12932. doi: 10.1039/c8ra01510d. eCollection 2018 Apr 3.

Authors

Kyungchan Min¹, Kyoung Soon Choi², Wook Jin Jeon¹, Dong Kyu Lee¹, Sein Oh¹, Jouhahn Lee², Jae-Young Choi³, Hak Ki Yu¹

Affiliations

¹ Dept. of Materials Science and Engineering & Dept. of Energy Systems Research, Ajou University Suwon 16499 Korea hakkiyu@ajou.ac.kr +82(0)31-219-1613 +82(0)31-219-1680.
² The Advanced Nano Surface Research Group, Korea Basic Science Institute Daejeon 34144 Korea.
³ School of Advanced Materials Science & Engineering, School of Advanced Institute of Nanotechnology (SAINT), Sungkyunkwan University Suwon 16419 Korea jy.choi@skku.edu.

Abstract

Herein, we fabricated a super-hydrophobic SERS substrate using Sn-doped indium oxide (Indium-tin-oxide: ITO) nano-branches as a template. ITO nano-branches with tens of nanometer diameter are first fabricated through the vapor-liquid-solid (VLS) growth to provide roughness of the substrate. 10 nm thickness of Ag thin film was deposited and then treated with the post-annealing process to create numerous air-pockets in the Ag film, forming a hierarchical Ag nanostructures. The resulting substrate obtained Cassie's wetting property with a water contact angle of 151°. Compared to the normal hydrophobic Ag nanoparticle substrate, increase of about 4.25-fold higher SERS signal was obtained for 7 μL of rhodamine 6G aqueous solutions.