Enhanced Photocatalytic Properties of g-C_3N_4/ZnO/Attapulgite (CNZATP) Composite Nano-Mineral Materials on Methylene Blue Dye Degradation

摘要

A nano-ZnO semiconductor material loaded with mineral attapulgite (ATP) photocatalyst has been investigated. Using ATP as a carrier, a variety of various mixtures of ZnO/ATP composites was synthesized. A scanning electron microscope (SEM), X-ray diffractometry (XRD), and UV-Vis spectrophotometer (UV-Vis) were used to examine the morphology, syner-gistic effects, and photocatalytic properties of ZnO/ATP nanocomposites. The target pollutant for photocatalytic degradation is methylene blue solution. When ATP is mixed with pure ZnO, the degrading performance of composite nanomaterials in methylene blue solution is considerably enhanced. The degree of methylene blue degradation increases as the amount of ATP in the composite grows, and the degradation rate of ZnO/40% ATP can reach 96% in 45 min under solar light illumination. The amount of ATP in the system is excessive, and the adsorption effect is visible. The optimal composite ratio was determined to be ZnO/30% ATP. After discovering the ideal composite ratio and synergy of ZnO/ATP, g-C_3N_4 was compounded in the aforesaid system, dramatically increasing the composite's photocatalytic activity. At 45 min, the degradation rate of methylene blue reaches 97%. The absorption range and intensity of ternary composites increased, and the pho-togenerated electron-hole recombination rate decreases significantly. The reaction rate constant increases from 0.033 to 0.069 min~(-1). SEM revealed rod-like attapulgite particles packed with tiny zinc oxide particles and a moderate layered structure of C_3N_4. The XRD pattern indicated that C_3N_4's crystallinity is poor and ZnO's peak intensity is excessively high, masking the composite material's distinctive peaks. The degradation rate of g-C_3N_4/ZnO/30% ATP to methylene blue was found to be 91.5% after 5 cycles.