The Correlation between Structural and Optical Properties of Zinc Hydroxide Nanoparticle in Supports Photocatalytic Performance

Abstract

- Green synthesized Zn(OH)2 mediated by Coleus blumei Benth leaf for pH: 4, 7, 10 and for calcination temperature: 400 °C, 450 °C, 500 °C, 550 °C, and 600 °C have been characterized by using Fourier transform infra-red (FTIR), ultraviolet–visible (Uv–Vis), and X-ray diffraction (XRD). The bonding formation present Zn– O –H, H– O –H, O –H, and Zn–O indicated Zn(OH)2 nanocrystal successfully synthesized. The optical, dielectric properties, and energy loss function were quantitatively determined from the FTIR spectra by using Kramers-Kronig (KK) dispersion relation. The distance between longitudinal (LO) and transverse (TO) optical phonon vibration mode Δ (LO-TO) and the bandgap increases with increasing the calcination temperature for all pH due to the amount of covalent bond is increase. The best calcination temperature is 600 °C and pH 7 indicated by the rate of the degradation performance is faster than the other temperature and pH. In this study shows FTIR spectra effective ways for determining the optical and dielectric properties, optical phonon vibration mode, and energy loss function of Zn(OH)2 material. • The Zn-O-H, H-O-H, O-H, and Zn-O bonding indicated formed of Zn(OH) 2 nanocrystal. • The n and k , ε 1 and ε 2 (ω), Im ( - 1 / ε 1 ( ω ) ) determined from FTIR spectra by applying K-K relation. • Distance optical phonon vibration (D(LO-TO)) is increases with increasing the calcination temperature for all pH. • The band gap increase with increasing the calcination temperature. • The best calcination temperature for photocatalyst is 600 o C.