Novel bilayer 2D V₂O₅ as a potential catalyst for fast photodegradation of organic dyes

Two-dimensional (2D) materials have recently drawn interest in various applications due to their superior electronic properties, high specific surface area, and surface activity. However, studies on the catalytic properties of the 2D counterpart of V₂O₅ are scarce. In the present study, the catalytic properties of 2D V₂O₅ vis-à-vis bulk V₂O₅ for the degradation of methylene blue dye are discussed for the first time. The 2D V₂O₅ catalyst was synthesized using a modified chemical exfoliation technique. A massive increase in the electrochemically active surface area of 2D V₂O₅ by one order of magnitude greater than that of bulk V₂O₅ was observed in this study. Simultaneously, ~ 7 times increase in the optical absorption coefficient of 2D V₂O₅ significantly increases the number of photogenerated electrons involved in the catalytic performance. In addition, the surface activity of the 2D V₂O₅ catalyst is enhanced by generating surface oxygen vacancy defects. In the current study, we have achieved ~ 99% degradation of 16 ppm dye using the 2D V₂O₅ nanosheet catalysts under UV light exposure with a remarkable degradation rate constant of 2.31 min^-1, which is an increase of the order of 10² from previous studies using V₂O₅ nanostructures and nanocomposites as catalysts. Since the enhanced photocatalytic activity emerged from the surface and optical properties of the catalyst, the current study shows great promise for the future application of 2D V₂O₅ in photo- and electrocatalysis.