1. Ag-Vanadates/GO Nanocomposites by Aerosol-Assisted Spray Pyrolysis: Preparation and Structural and Electrochemical Characterization of a Versatile Material
- Author
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Gian Andrea Rizzi, Shuang Shuang, Gaetano Granozzi, Leonardo Girardi, Carla Marega, Jian Zheng, Laura Calvillo, Carlos Valero-Vidal, Stefano Agnoli, and Pandiaraj Sekar
- Subjects
Paper ,Diffraction ,Electric properties ,Electric transport processes and properties ,Electrochemical analysis ,Heat treatment ,Spectra ,Surface structure ,Materials science ,General Chemical Engineering ,Oxide ,Analytical chemistry ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Article ,law.invention ,lcsh:Chemistry ,chemistry.chemical_compound ,symbols.namesake ,law ,Nanocomposite ,Graphene ,General Chemistry ,021001 nanoscience & nanotechnology ,Tin oxide ,0104 chemical sciences ,Dielectric spectroscopy ,lcsh:QD1-999 ,Chemical engineering ,chemistry ,Linear sweep voltammetry ,symbols ,0210 nano-technology ,Raman spectroscopy - Abstract
In this article, we describe the deposition by aerosol-assisted spray pyrolysis of different types of silver vanadate nanocomposites with and without graphene oxide (GO) on different substrates (carbon paper (CP) and fluorine-doped tin oxide (FTO)). When deposited on CP, different amounts of GO were added to the Ag and V precursor solution to study the effect of GO on the physicochemical properties of the resulting Ag-vanadate. It is shown that the addition of GO leads mainly to the formation of nanoparticles of the Ag2V4O11 phase, whereas Ag2V4O11 and Ag3VO4 are obtained without the addition of GO. The morphology and chemical properties of the composites were determined by scanning and transmission electron microscopies, X-ray diffraction, X-ray photoemission spectroscopy, and UV–visible and Raman spectroscopies. In addition, the photoelectrochemical (PEC) properties of such composites were studied by CV, linear sweep voltammetry, and electrochemical impedance spectroscopy. The ideal AgxVOy and GO ratio was optimized for obtaining higher photocurrent values and a good stability. The results showed that the presence of GO improves the electrical conductivity of the catalyst layer as well as the electron injection from the oxide to the electrode surface. The deposition of pure Ag2V4O11 on FTO does not lead to samples with stable PEC performances. Samples grown on CP supports showed an efficient electrochemical detection of small amounts of ethylenediamine in water solution.
- Published
- 2017