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Carbon-doped g-C 3 N 4 (CGNS) nanocomposite with Ag 2 O and α-Fe 2 O 3 has been synthesized to improve g-C 3 N 4 photocatalytic activity. The prepared CGNS/Ag 2 O/α-Fe 2 O 3 (GAF [with mass ratio 3:2:1]) nanocomposite exhibits the expanded visible-light absorption region leading to the enhanced photocatalytic performance for Acid Red 14 (AR14) degradation. Besides, it is found that the recombination rate of the charge carriers effectively suppresses the nanocomposite. For a better understanding of the photocatalytic degradation mechanism, the reactions have been performed in the presence of different scavengers. The experiments indicate that superoxide anion radicals possess a more influential role in AR14 degradation in comparison with hydroxyl radicals and holes. The degradation efficiency has been decreased from 94.68 to 85.60 after five consecutive photocatalytic tests implying that the prepared nanocomposite is a stable photocatalyst. In the end, the kinetic study of AR14 degradation on nanocomposite with considering pseudo-first-order kinetics results in a nonlinear empirical kinetic model development for prediction of degradation efficiency of AR14 on nanocomposite.

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This paper investigates the optical properties of the two plasma photonic crystal structures. The first structure contains periodic thin layers of plasma with heterogeneous densities, and in the second one, the heterogeneous plasma layer has been applied as the defect layer of a one-dimensional photonic crystal. Herein, the plasma density distribution function is considered a continuous function of plasma critical density as follows: n = n cr f ( r → ) , where n cr = m e ε 0 ω 2 / e 2 represents the critical density of the plasma and f ( r → ) indicates the plasma density distribution function. The heterogeneous plasma layer is assumed to be composed of several homogeneous sublayers with constant density. The transfer-matrix method is applied in calculations, and the total transfer matrix is obtained by multiplying the transfer matrices of each sublayer. Properties and behavior of the photonic bandgap and the defect mode for five different plasma density distribution functions and applied external constant magnetic field are comparatively investigated. Results show that, in the first structure, increasing the incident angle from 0° to 30° causes a bandgap shift to higher frequencies. So, the incident angle is a parameter that can control the bandgap. In the defective structure, the intensity of the defect modes is almost the same in all five distributions, but their locations in the spectrum are different. The effect of the lateral position of the maximum density and external constant magnetic field on the defect mode position is also investigated. The capability of controlling the photonic bandgaps and defect modes of the plasma photonic crystals creates wide applications in promising tunable optical devices, such as optical filters.