Shaping in the Third Direction; Fabrication of Hemispherical Micro-Concavity Array by Using Large Size Polystyrene Spheres as Template for Direct Self-Assembly of Small Size Silica Spheres

Ion Sandu; Claudiu Teodor Fleaca; Florian Dumitrache; Bogdan Alexandru Sava; Iuliana Urzica; Iulia Antohe; Simona Brajnicov; Marius Dumitru

doi:10.3390/polym14112158

Shaping in the Third Direction; Fabrication of Hemispherical Micro-Concavity Array by Using Large Size Polystyrene Spheres as Template for Direct Self-Assembly of Small Size Silica Spheres

Polymers (Basel). 2022 May 26;14(11):2158. doi: 10.3390/polym14112158.

Authors

Ion Sandu¹, Claudiu Teodor Fleaca¹, Florian Dumitrache¹, Bogdan Alexandru Sava^{1

2}, Iuliana Urzica¹, Iulia Antohe¹, Simona Brajnicov¹, Marius Dumitru¹

Affiliations

¹ National Institute for Lasers, Plasma and Radiation Physics, Lasers Department, 409 Atomistilor Street, 077125 Bucharest, Romania.
² Faculty of Applied Chemistry and Materials Science, University Politehnica of Bucharest, 313 Splaiul Independenţei Street, Sector 6, 060042 Bucharest, Romania.

Abstract

Silica and polystyrene spheres with a small size ratio (r = 0.005) form by sequential hanging drop self-assembly, a binary colloidal crystal through which calcination transforms in a silica-ordered concavity array. These arrays are capable of light Bragg diffraction and shape dependent optical phenomena, and they can be transformed into inverse-opal structures. Hierarchical 2D and 3D super-structures with ordered concavities as structural units were fabricated in this study.

Keywords: colloidal crystal; concavity; self-assembly; shape; super-structure.

Abstract

Grants and funding