Síntese de heterojunções CaMoO4/g-C3N4 e avaliação de suas propriedades fotocatalíticas para degradação de corantes

Abstract

The development of efficient photocatalysts for environmental pollution caused by textile dyes continues to be a challenge to be resolved. In this sense, the combination of two materials forming heterojunctions in order to improve the characteristics of both, and their photocatalytic application appears as something promising. In this work, the microwaveassisted hydrothermal synthesis of CaMoO4/g-C3N4 (CMO/CN) type II heterojunctions is reported, varying the synthesis time (between 15 and 60 minutes) and the molar percentage of g-C3N4 between 40 and 70%). The samples were characterized by the techniques of X-ray Diffraction, Diffuse Reflectance Spectroscopy in the UV-Visible region, Raman Spectroscopy, Photoluminescence, Field Emission Scanning Electron Microscopy, X-ray Photoelectron Spectroscopy, Adsorption-Desorption Isotherms of Nitrogen and Electron Paramagnetic Resonance Spectroscopy. The photocatalytic activity of CaMoO4/g-C3N4 heterojunctions was evaluated in the degradation of methylene blue and crystal violet dyes under ultraviolet light irradiation. Furthermore, reuse tests aiming at photocatalytic stability, scavenger tests in order to observe the active radicals and tests under simulated visible light irradiation and sunlight in order to analyze the influence of the light source on the degradation efficiency were carried out.