Facile preparation of core/shell Ag/Fe3O4@MIL-100(Fe) with Ag plasmon-enhanced photo-Fenton activity towards RhB degradation

Facile Preparation of Magnetically Separable Fe3O4/ZnO Nanocomposite with Enhanced Photocatalytic Activity for Degradation of Rhodamine B

“…It also revealed that a few hydroxide radicals were adsorbed on the surface of the composite material, which would make a contribution to high photocatalytic performance for RhB degradation by facilitating the generation of active ·OH radicals. The distinct peak at 568 cm −1 indicates the stretching vibrations of the Fe-O bond [ 30 , 34 ]. The Zn-O stretching vibration is not detected because of the relatively low crystallinity of the composite.…”

“…As shown in Figure 10 c, the high-resolution XPS spectrum of Zn 2p showed two peaks at 1046.18 and 1022.99 eV belonging to the Zn 2p 1/2 and Zn 2p 3/2 orbitals of ZnO, indicating the presence of Zn 2+ in the composite [ 7 ]. In the O 1 s spectrum ( Figure 10 d), there are also three peaks at 532.13 eV, 530.57 eV, and 528.98 eV, which are related to ZnO and Fe 3 O 4 , respectively [ 8 , 14 , 24 , 30 ]. By comparing the data to the fresh samples, it could be found there were obvious chemical and structure changes in the Fe 3 O 4 /ZnO composite due to the overflow of Fe atoms from the lattice to the surface, which would decrease the catalytic activity of Fe 3 O 4 /ZnO.…”

“…The peaks observed at 2θ = 31.7°, 34.4°, 36.2°, 47.5 62.8°, and 67.9° in the Fe3O4/ZnO sample are closely ascribed to those of the Zn (JCPDS: 36-1451) [6,21,35]. Additionally, the peaks recorded at 2θ = 18.2°, 30.1 37.0°, 43.1°, 56.9°, and 62.5° in the Fe3O4/ZnO sample correspond to the distinct diff peaks of Fe3O4 crystal planes (111), ( 220), (311), ( 222), (400), (511), and (440), co with pure Fe3O4 pa erns (JCPDS: 19-0629) [30,32]. The results suggested the pre pure ZnO components and validated the successful coating of Fe3O4 onto the ZnO For comparison, the intensity of the diffraction peak in Fe3O4/ZnO is weaker than ZnO and stronger than that in commercial Fe3O4.…”

“…Figure 7a,b illustrates the photocatalytic performance and degradation rates for RhB removal under UV-light illumination over Fe 3 O 4 /ZnO prepared with different pH values. The degradation kinetics were described by a pseudo-first-order rate equation −ln(C t /C 0 ) = kt [14,30], where k denotes the pseudofirst-order rate constant (min −1 ), C 0 represents the initial RhB concentration, and C t denotes the concentration at time t. Figure 8a shows that the initial pH value of the suspension does not significantly impact the absorption and degradation of RhB. When comparing the degradation rates in Figure 8b, it is clear that the highest photocatalytic degradation rate of RhB (0.081 min −1 ) occurs at an initial pH of 10.…”

“…This allows a higher number of photogenerated electrons and holes to facilitate the decomposition of pollutant molecules, ultimately enhancing the catalytic activity of nanocomposites [ 28 ]. The other key problems with photocatalysts are recoverability and reusability, which lead to significant financial losses and pollution due to the laborious recovery process, impeding the commercialization of photocatalytic technology [ 30 , 31 , 32 , 33 ]. In summary, it can be seen that the high recombination rate of photogenerated carriers is the main factor limiting the performance of photocatalysts.…”