Abstract
Cold crystallization of SnO2 was realized in aqueous solutions, where crystal growth was controlled to form SnO2 (101) nanosheet assembled films for devices such as chemical sensors. The nanosheets grew directly on a fluorine-doped tin oxide substrate without a seed layer or a buffer layer. The nanosheets had a thickness of 5–10 nm and an in-plane size of 100–1600 nm. Moreover, the large flat surface of the (101) facet was metastable. The thickness of the SnO2 (101) nanosheet assembled film was approximately 800 nm, and the film had a gradient structure that contained many connected nanosheets. TEM results revealed that the predominate branch angles between any two connected nanosheets were 90° and 46.48°, corresponding to type I and type II connections, respectively. These connections were consistent with the calculations based on crystallography. Crystallographic analysis clarified the characteristic crystal growth of the SnO2 (101) nanosheet assembled film in the aqueous solution. Furthermore, we demonstrate that the metastable (101) facet can be exploited to control the rate of crystal growth by adjusting the etching condition.
Highlights
Metal oxide nanostructures have been developed on fluorine-doped tin oxide (FTO) substrates for various devices such as chemical s ensors[1,2,3]
The results suggested that the sensing mechanism of S nO2 for polar VOCs at room temperature can be explained by their direct adsorption on the surface rather than through their oxidation by ionosorbed oxygen species
Film formation was realized at room temperature and atmospheric pressure in the aqueous solution with an open-air system
Summary
Metal oxide nanostructures have been developed on fluorine-doped tin oxide (FTO) substrates for various devices such as chemical s ensors[1,2,3]. The FTO substrate possessed high transparency, which was essential for the transmission of excitation light. Compared to an indium-doped tin oxide (ITO) transparent conductive film, the FTO film had a large surface roughness and a high surface area, which were effective at increasing the adsorption of dye-labeled monoclonal antibody. A photoelectric conversion molecular sensor has been developed using T iO2 nanostructured films on a FTO substrate[4,5]. The nanostructured T iO2 film, covered with dye-labeled proteins[5], showed high photoluminescence and a photocurrent of 4 nA under an excitation light of 633 nm in wavelength. The high surface area and internal nanospace of the SnO2 (101) nanosheet assembled films were effective at enhancing the performance of the molecular sensor. The sensor can be used for the detection of hepatocellular cancer
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
