Development of tungsten trioxide nanoparticles for catalytic and water remediation applications

Abstract

Energy and fresh water are two of the most basic and essential elements of nature, and are two of the most rapidly depleting resources on the planet. This is due to extensive industrialization, excessive consumption, and overpopulation. Water is the basic need for life to survive, and approximately 70 % of the earth is covered with this precious component. However, it is very regrettable to discuss that less than 0.5 % of the earth is available as fresh water. Around 1.3 billion people on this planet face severe water scarcity because they lack access to fresh and drinkable water. As a result of rapid industrialization and irresponsible human activities, many different types of pollutants are being thrown directly into the water distribution system, including inorganics, organics, and biological. Fortunately, over the past few years, many researches and a variety of approaches have been explored to develop efficient and pollution-free technology to convert highly polluted and toxic water pollutants to non-toxic products for waste water management. Among many technologies, photocatalysis has emerged as one of the most efficient and eco-friendly, as it represents a green and economical way to demineralize pollutants by using sunlight energy or energy from an artificial source of light. As well as removing organic pollutants (like dyes, pesticides, herbicides, and phenolic compounds), heavy metals, and harmful bacteria and fungi, photocatalysis is also effective at removing heavy metals.The removal of organic contaminants from water systems via photocatalytic degradation has gained popularity as a promising method. Using WO3, ortho hydrated tungsten trioxide, WO3/g-C3N4 (before and after annealing), and WO3/exfoliated g-C3N4 (before and after annealing), the photocatalytic degradation of Rhodamine B (RhB) dye was examined in this study. The objective was to assess the effectiveness of photocatalysts in the degradation of hazardous RhB dye and explore the synergistic interactions between tungsten trioxide nanoparticles with graphitic carbon nitride and exfoliated graphitic carbon nitride. The pristine tungsten trioxide and the nanocomposites were synthesized using a facile hydrothermal method. Powder X-ray diffraction (PXRD), Field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), Photoluminescence spectroscopy (PL), and UV-VIS DRS were used to assess the structural, morphological, compositional, and optical characteristics of the photocatalysts. The outcomes showed that the most improved photocatalytic activity was observed in tungsten trioxide/exfoliated graphitic carbon nitride photocatalyst about 89.13 % in 30 minutes duration. RhB dye degradation took place when it was exposed to visible light. The concentration of RhB dye was monitored at regular intervals using UV-Visible spectroscopy. According to the experimental findings, pristine tungsten trioxide and its nanocomposites both exhibited considerable photocatalytic activity towards the breakdown of RhB. Exfoliated graphitic carbon nitride may have synergistic effects with tungsten trioxide, as evidenced by the nanocomposite's improved degradation efficiency when compared to all other synthesized samples. The photocatalytic process followed pseudo first order kinetics and the degradation rate constants were determined. Thus, by incorporating exfoliated g-C3N4 with WO3 enhances the photocatalytic performance indicating the potential of this nanocomposite for the treatment of organic pollutant in waste water treatment. The results of this study aid in the creation of effective and long-lasting photocatalytic materials for use in environmental remediation applications.The synthesized samples have been considered to very active catalyst, because it can use visible light as an excitation source, it can also use solar radiation for future wastewater treatment and energy generation applications.