Electrical, dielectric and photocatalytic properties of Fe-doped ZnO nanomaterials synthesized by sol gel method

Abstract

Fe-doped ZnO nanoparticles were synthesized by sol gel technique. Fine-scale and single phase hexagonal wurtzite structure in all samples were confirmed by SEM and XRD, respectively. The band gap energy depends on the amount of Fe and was found to be in the range of 3.11-2.53 eV. The electric and dielectric properties were investigated using complex impedance spectroscopy. AC conductivity data were correlated with the barrier hopping (CBH) model to evaluate the binding energy (W m ), the minimum hopping distance (R min ) and the density of states at Fermi level, N(E F ). Fe doping in ZnO also improved the photocatalytic activity. Thus, the sample Zn 0.95 Fe 0.05 O showed high degradation potential towards methylene blue (MB), i.e. it degrades 90% of BM in 90 min under UV light.

Structural, morphological, magnetic and electrical properties of Ni-doped ZnO nanoparticles synthesized by co-precipitation method

“…The electrical characteristic of a material is exhibited by the appearance of semicircular arcs in Nyquist plots. Figure 13 shows the complex impedance plots (Nyquist plots) of pure and Ni-doped ZnO nanoparticles and similar behaviour is given by Cherifi et al [44] and Omri et al [48]. It has been reported in literature that the resistivity of a polycrystalline material, in general, increases with the decrease in grain size.…”

“…Thus, the term A·ω s in Eq. 5 can often be elucidated on the basis of two distinct mechanisms for carrier conduction [44,45]: i) quantum mechanical tunnelling (QMT) through the barrier separating the localized sites near the Fermi level, ii) correlated barrier hopping (CBH) over the same barrier that is defined as a sudden displacement of a charge carrier from one to another neighbouring position and generally includes both jumps over a potential barrier separating them rather than tunnelling through the barrier. Further, at particularly high temperatures the orientation polarization is the dominant mechanism while at low frequencies, the hopping electrons are trapped by structural inhomogeneities existing in the crystal structure.…”

The investigation of mechanical and dielectric properties of Samarium doped ZnO nanoparticles

“…For pure and Sm-doped ZnO samples, the dielectric constants (ε′ and ε″), dielectric loss (tan δ) and ac conductivity (σ ac ) are measured by changing the frequency at a specific temperature. The reliance of dielectric parameters on frequency and temperature is useful in structural changes, transport mechanism and defect behavior of a solid [43]. The polar molecule ZnO, exhibiting a permanent dipole moment, is sensitive to external ac electric filed.…”

Recent Advances in Zinc Oxide Nanostructures with Antimicrobial Activities

“…Under solar light irradiation, Fe 3+ ions acted as the hole and electron traps, thus promoting the ROS generation. The photocatalytic reactions were given by [308], Fe 3+ + e − → Fe 2+ (electron trap)…”

“…Under solar light irradiation, Fe 3+ ions acted as the hole and electron traps, thus promoting the ROS generation. The photocatalytic reactions were given by [308], Fe 3+ + e − → Fe 2+ (electron trap) The decline in bacterial populations due to Fe/ZnO NPs was attributed to the generation of superoxide and hydroxyl radicals, leading to membrane lipid peroxidation as revealed by the MDA results (Figure 39a), and the leakage of of K + ion from MDR E. coli (Figure 39b). i.e., ZnO:TFA 1:1 and ZnO:TFA 1:2, were prepared by the sol-gel process [310].…”