Effect of Precursor Concentration on Physical Properties of Cube-Like Zn2SnO4 Powders Synthesized by Co-Precipitation Method

Abstract

Cube-like Zinc stannate (Zn2SnO4) spinel powders were synthesized by co-precipitation method using chloride starting precursors of zinc and tin. The influence concentration of precursors on relevant physical properties of Zn2SnO4 was investigated by increasing concentration of precursor material at 0.1 to 0.4 M (Zn:Sn at ratio 1:1). Structural properties of as-synthesized and Zn2SnO4 crystal were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray absorption spectroscopy (XAS). The results indicate that as-prepared material without calcination process is in cubic symmetry of zinc hydroxy stannate (ZnSn(OH)6) affirmed by SEM and XRD results. Meanwhile, spinel phase of Zn2SnO4 with strong crystalline and eminent cubic structure can be achieved after calcination at 1000°C. Homogenous dispersion, high crystallinity and good cubic structure of Zn2SnO4 powders are occurred at higher concentration of precursors. Moreover, the oxidation state of these samples were investigated by the Zn K-edge and Sn L3-edge X-ray absorption near edge structure (XANES) using the synchrotron radiation light source. The analyses of XANES spectra revealed that the oxidation state of Zn was +2 and Sn valence was +4 in all Zn2SnO4 samples, which well corresponds to the theoretical values.