Electrodeposition and electrocatalytic characteristics of porous crystalline SnO2 thin film using butyl-rhodamine B as a structure-directing agent

Abstract Porous crystalline SnO 2 thin films were electrodeposited from an oxygen-saturated acid aqueous solution of SnCl 2 containing different amounts of butyl rhodamine B (BRhB) at 70 °C. BRhB can not only be dissolved in the acid deposition solution due to its amidocyanogen substitute, where HCl was added to suppress hydrolysis of SnCl 2 , but also be adsorbed on the surface of SnO 2 through its carbonate substitute. Therefore, it was used as a structure-directing agent to control the growth of SnO 2 crystals and then the crystalline structure and surface morphology of the deposited film. The electrodeposited thin films show porous morphology and rutile-type SnO 2 crystalline structure due to the effects of BRhB on the growth, and these structural features can be adjusted by changing the added amount of BRhB. The SnO 2 thin film electrodeposited with addition of BRhB exhibits electrocatalytic characteristic enhancement on oxidation of phenol due to its porous structure.