Sustainable one-pot integration of ZnO nanoparticles into carbon spheres: manipulation of the morphological, optical and electrochemical properties. Issue 44 (1st November 2016)

• Record Type: Journal Article
• Authors: Patrinoiu, Greta; Calderon-Moreno, Jose M.; Birjega, Ruxandra; Culita, Daniela C.; Somacescu, Simona; Musuc, Adina M.; Spataru, Tanta; Carp, Oana
• Is Part Of: Physical chemistry chemical physics. Volume 18:Issue 44(2016)
• Page Start: 30794
• Page End: 30807
• Publication Date: 2016-11-01
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/c6cp05911b
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Tailored ZnO–C composite spheres were developed using a sustainable and scalable hydrothermal procedure with the appropriate subsequent thermal processing. Abstract : ZnO–carbon composite spheres were synthesized via starch hydrothermal carbonization (HTC) in the presence of a soluble zinc salt (acetate), followed by thermal processing under an argon atmosphere. Besides sustainability, the one-pot procedure represents a scalable synthesis of tailored carbon–metal oxide spheres with a structurally-ordered carbon matrix obtained at a relatively low temperature (700 °C). The ability of zinc cations to develop different linkages with starch's hydrophilic functional groups and to act as external nucleators determines an increase in HTC yield; the effect is obvious even in the presence of small concentrations of zinc in the reaction medium (0.005 M), thus providing a way to improve the carbonization process efficiency. It is also shown that zinc content is the control vector of the spherical composite's properties: a variation from 0.3 to 4.8 at% not only induces a variation in their size (200 nm–10 μm), interconnectivity (from disperse spheres to necklace-like aggregations), surface area and connected porosity (from micro- to mesoporosity), but also of their electrochemical and white light adsorption and emission features. Since the variation in zinc content is made by a simple adjustment of the raw material concentrations, the functionality of these carbon-based materials can be modulated in a straightforward manner.