Advancing photocatalytic activity through a green route: Bismuth ferrite@molybdenum trioxide heterostructure for sustainable water treatment
M.A. Bukhari, Syed Muhammad Zubair Shah Bukhari, Muhammad Yasir Khalid, Zia Ullah Arif
Abstract
Photocatalysis has become increasingly pervasive in the chemical industry, profoundly impacting operational costs. However, an ideal photocatalyst must possess characteristics such as excellent reactivity, high selectivity, prolonged stability, low toxicity, and cost-effectiveness. Moreover, it should facilitate the efficient separation of photo-generated charge carriers, thereby minimizing recombination rates. In pursuit of advancing photocatalytic activity for sustainable water treatment, this investigation focused on synthesizing a groundbreaking photocatalyst, the Bismuth Ferrite@Molybdenum trioxide heterostructure, using an eco-friendly green chemistry technique with pomegranate extract. This approach aligns with the goal of environmental sustainability and represents a novel contribution to the field. Employing a comprehensive approach, advanced characterization techniques such as XRD, SEM, FT-IR, and UV-Vis were applied to analyze the material's structural, morphological, and optical properties. According to the characterization results, the heterostructure demonstrates superior photocatalytic efficiency, heightened crystallinity, and reduced recombination rates during dye degradation for water treatment compared to both individual photocatalysts. Notably, the composite catalyst exhibits a synergistic impact, outperforming individual BiFeO3 and MoO3 photocatalysts. SEM observations confirm the successful integration of rod-like MoO3 and cylindrical BiFeO3 morphologies, highlighting the strategic combination achieved through the green chemistry route. Furthermore, UV-Vis spectroscopy reveals key optical parameters, emphasizing a narrow bandgap energy of 2.74 eV with a high refractive index of 2.43 eV. The exceptional efficacy of the heterostructure in degrading dyes within the visible spectrum, surpassing expectations within a 4-hour timeframe, highlights its efficiency and precision. Remarkably, achieved degradation rates for Rhodamine B dye (98%), Methyl Blue (96%), and Methyl Orange dye (95%) underscore the promising potential of this developed photocatalytic system in effectively addressing water pollutant challenges. In addition to the findings highlighted above, it is noteworthy that this study represents the first exploration of the heterostructure of BiFeO3 with MoO3 photocatalysts. Moreover, the use of pomegranate extract in the green synthesis process underscores our commitment to environmental sustainability. The choice of a type two semiconductor photocatalysts enhances electron-hole pair separation, leading to a more efficient flow of electrons and holes and resulting in lower recombination rates, thus contributing to the superior performance of the heterostructure for degradation of dyes.