Figure 7:

SEM images of surface morphology (A) and cross-section (B) of the 10-cycle (PDDA/SiO2) film overlay deposited on a quartz substrate as preliminary test. SEM image of cross-section (C) of the same film overlay (one cycle) deposited onto the optical fiber containing an LPG.

Figures adapted with permission from Ref. [42]. Copyright (2012) Elsevier.

© De Gruyter