Effect of boric acid composition on the properties of ZnO thin film nanotubes and the performance of dye-sensitized solar cell (DSSC)

• Boron was doped into ZnO films by adding H3BO3 into the growth solution.
• Diameter and thickness of ZnO nanotubes decreases with the composition of H3BO3.
• The DSSC performs the highest JSC and η of 2.67 mA cm−2 and 0.29%, respectively.
• This is due to high specific surface area and low charge interfacial resistance.

The effect of boric acid (H3BO3) composition at constant concentration of hexamethylenetetramine (HMT) and zinc nitrate (Zn(NO3)2) on the morphology, thickness, elemental composition, optical absorption, structure, photoluminescence of ZnO nanotubes has been investigated. The performance of the DSSC utilizing the ZnO samples has also been studied. It was found that the structure, thickness, elemental composition, optical absorption and morphology of ZnO nanostructure are significantly affected by the concentration of H3BO3. The diameter and thickness of ZnO nanotubes decreases as the composition of H3BO3 increases. The DSSC utilizing ZnO nanotubes synthesized at 2 wt. % H3BO3 performs the highest JSC and η of 2.67 mA cm−2 and 0.29%, respectively. The highest performance of the device is due to the highest optical absorption of ZnO nanotubes sample and lowest charge interfacial resistance.

Nyquist plots of the DSSCs utilizing ZnO nanotubes prepared at various boric acid compositions.Figure optionsDownload as PowerPoint slide