Fig. 2: CNT film thickness control.

a Top-view SEM image (inset: digital image of CNT/FTO electrode) and b magnified top-view SEM image of CNT film. c Cross-sectional SEM images of the different thicknesses CNT films on FTO. d Relationship between the final thickness of CNT films and the corresponding thiourea layers. Each data point represents an average of three different CNT electrodes; error bars represent standard deviation.