Study on the Adsorption Mechanism of 2,4-D Molecules on the Surface of Cu Rectangular Structures: A Molecular Dynamics Simulation

As a widely utilized herbicide, 2,4-D has been extensively employed on a global scale. However, its widespread utilization raises concerns regarding its environmental impact and potential health hazards. The adsorption mechanism of 2,4-D molecules on Cu substrate surfaces was investigated by molecular dynamics (MD) simulations. The attention was focused on effect of surface morphology on the adsorption efficacy of 2,4-D. In order to investigate the adsorption process of 2,4-D molecules on rectangular grooves, an analysis was conducted on the distribution of surface 2,4-D molecules, the number of atoms within the grooves, density distribution, and the centroid positions. The findings shows the variation in both the width and depth of the rectangular grooves on the Cu substrate significantly impacts the adsorption effectiveness of 2,4-D molecules. Increasing the width allows for the 2,4-D molecules to spread over a larger surface area, while enlarging the depth facilitates more 2,4-D molecules to enter the grooves, resulting in a smaller horizontal distribution area and a predominant concentration in the vertical direction. Additionally, it was observed that the 2,4-D molecules are distributed on the surface of the substrate in a layered structure. The distribution of 2,4-D molecules on the substrate surface is divided into three layers. The density of 2,4-D distribution is greater in the lower layers, correlating with a higher number of distribution. The width and depth of the rectangular groove structure on the substrate have an impact on the distribution of the 2,4-D molecular layers. As the groove depth and width increase, the 2,4-D molecules come closer to the surface, resulting in a better surface adsorption effect.