Preparation, characterization and electrical properties of fluorine-doped tin dioxide nanocrystals

• Published in: Journal of colloid and interface science Vol. 346; no. 1; pp. 12 - 16
• Main Authors: Wu, Shanshan, Yuan, Shuai, Shi, Liyi, Zhao, Yin, Fang, Jianhui
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 01.06.2010; Elsevier
• Subjects: Chemistry; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Colloids; Electrical resistivity; Electrochemistry; Exact sciences and technology; Fluorides - chemistry; Fluorine; Fluorine doped SnO 2; General and physical chemistry; Nanocrystals; Nanoparticles - chemistry; Particle Size; Quaternary Ammonium Compounds - chemistry; Resistance; Surface Properties; Tin; Tin Compounds - chemical synthesis; Tin Compounds - chemistry; Tin dioxide; Tin oxides; X-ray photoelectron spectroscopy; X-rays; Resistance; Nanocrystals; Colloids; Fluorine doped SnO 2; Binary compound; High resolution; Fluorine; Rutile; X ray; Powder; Characterization; Hydrothermal treatment; Technology; Tin oxide; Electrokinetic potential; Photoelectron spectrometry; Fluorine doped SnO; Structure; Diameter; Nanocrystal; Composition; Stability; Electrical properties; Nanostructure; X ray diffraction; Colloid; Transmission electron microscopy; Sol gel process; Preparation; Electrochemistry; Electric resistivity
• ISSN: 0021-9797; 1095-7103; 1095-7103
• DOI: 10.1016/j.jcis.2010.02.031

The HRTEM image and FFT pattern reveal that the fluorine doped SnO 2 nanocrystals are of cassiterite structure. Fluorine-doped tin dioxide (FTO) nanocrystals were prepared with a sol–gel process followed by a hydrothermal treatment using SnCl 4 and NH 4F as SnO 2 and fluorine dopant, respectively. The nanostructure and composition were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), zeta potential analysis, electrochemical measurement technology and X-ray photoelectron spectroscopy (XPS) respectively. The diameter of the fluorine doped SnO 2 nanocrystal in rutile-type structure is about 10 nm. Compared to the pure SnO 2 nanocrystals, the fluorine doped SnO 2 nanocrystals can be dispersed homogeneously in H 2O, forming transparent sol with high stability. The powder of fluorine doped SnO 2 nanocrystals could be obtained by removing the solvent, and the electrical resistivity properties were measured by a four-point probe measurement. The results show that sheet resistances (Rs) of fluorine doped SnO 2 decrease with the increasing NH 4F/Sn molar ratio in the range from 0 to 2. However, further increase of NH 4F/Sn molar ratio from 2 to 5 leads to higher sheet resistance. The F/Sn molar ratio of fluorine doped SnO 2 measured by XPS is about 0.18 when NH 4F/Sn molar ratio is equal to 2, and the sheet resistance of fluorine doped SnO 2 powder is 110Ω/□.