Fabrication of Z-Scheme TiO2/rGO/MoS2 Nanocomposite as an Efficient Photocatalyst for Methylene Blue Degradation

Water pollution is a big issue for the developing and developed nations. There have been great efforts by the government and other non-governmental organizations to supply clean and potable water to their population. In this regard, different techniques have been developed for the clean water supplies for the society at large. Among these approaches, visible light driven photo-catalysis are very promising for removal of hazardous organic pollutants from drinking water and waste water streams. This method is unique due to its effectiveness, ease and low cost. Most of the previous works on photo-catalytic removal of organic pollutants have been focused on metal oxide-based photo catalysts like TiO2, ZnO, WO3 etc. These catalysts have inherent problems and limitations due to wide band gap as well low efficiency as a result of electron hole recombination process. In order to overcome these draw backs, we propose to synthesize a novel Z-scheme TiO2/rGO/MoS2 nanocomposite consisting of TiO2 nanotube in which rGO act as an electron transfer mediator and MoS2 nanosheets having bandgap = 1.8 eV. Such nanocomposite catalyst would have a band gap in the visible region, will limit electron hole recombination process and will be ideal to use the sunlight for removal of organic pollutants. To the best of our knowledge, this will be the first attempt to prepare such an advanced nanocomposite photo-catalyst by using three major advanced process such as thermal, pulsed laser ablation technique and using microwave-assisted wet-chemical method for removal of environmental pollutants such as methylene blue (MB). There are three primary objectives for this proposal that principally address the strategic goals of the vision 2030. The first, main goal is to promote scientific research in the development of smart materials like visible light driven advanced nanocomposite photo-catalysts for purification of water in line with the Kingdom future clean water needs. The second goal is to develop the process and experimental setup locally. The third goal is to promote the promising research field of nanotechnology by training and teaching researchers and students in the highly valued subjects of water remediation, the environment, and nanotechnology and by providing opportunities for technology transfer. This study will also provide a technical basis for applied research work, and the outcome of this research will be very useful for industrial applications of water purification and could be beneficial for many governmental agencies responsible for supply of clean water, and other water purification companies in the Kingdom.