The contamination of water bodies with organic pollutants has become a pressing global environmental issue, posing severe risks to ecosystems and human health. Organic compounds, such as industrial dyes, pharmaceuticals, pesticides, and petrochemicals, are highly stable and resistant to conventional wastewater treatment methods, leading to their persistent accumulation in aquatic environments [1]. Among various remediation techniques, photocatalytic decomposition has emerged as a highly effective and environmentally friendly approach, utilizing semiconductor materials to harness solar energy and degrade organic pollutants into harmless byproducts. This method offers advantages such as complete mineralization of contaminants, low energy consumption, and the potential for large-scale applications.
Titanium suboxides (Ti\(_{n}\)nO\(_{2n-1}\)) have shown great promise due to their tunable bandgap, superior conductivity, and enhanced charge carrier dynamics, which improve photocatalytic efficiency under visible light illumination [2]. Recent studies from our group highlight that these materials demonstrate superior photocatalytic degradation of organic pollutants compared to traditional titanium dioxide (TiO\(_{2}\)) [3]. Additionally, core-shell nanostructures have emerged as an innovative strategy to further enhance photocatalytic performance. These structures, consisting of a photocatalytic core and a functional shell, offer improved charge separation, reduced recombination rates, and enhanced surface reactivity, leading to significantly higher pollutant degradation rates. By engineering core-shell architectures with synergistic material combinations, researchers have developed nanostructures that operate efficiently under visible light, making them highly attractive for wastewater treatment applications [4].
In this work, we explore the recent trends in the synthesis and design of titanium suboxides and core-shell nanostructures for photocatalytic wastewater treatment. We discuss their physicochemical properties, band structure engineering, and mechanisms that enhance photocatalytic activity. Our study demonstrates that both titanium suboxide materials and core-shell nanostructures exhibit significant potential for next-generation wastewater treatment technologies due to their improved charge transport, visible-light responsiveness, and superior degradation efficiency. These advancements pave the way for the development of highly efficient and sustainable photocatalytic systems for environmental remediation.