Fabrication of gold nanoantennas on SiO2/TiO2 core/shell beads to study photon-driven surface reactions

Plasmonic nanoantennas offer exciting perspectives for promoting and investigating light-driven chemical reactions. In particular, core/shell semiconductor beads coupled to gold nanoantennas represent an ideal platform for a systematic evaluation of multiple processes stimulated by light at different frequencies. Here we report the detailed fabrication of gold bowties on SiO2/TiO2 core/shell micro- and nano-beads, which is based on the combination of colloidal synthesis, atomic layer deposition and a modified version of induced deposition mask lithography. The critical steps of fabrication, including choice of mask material, etching rate and experimental setup are analyzed and strategies to pursue a successful fabrication of different nanoantennas are discussed.