DFT Calculations for Adsorption of Methylene Blue Dye on Neem (Azadirachta indica) Leaves

Organic dyes, present in the aquatic environment, have negative effects on ecosystems. Attempts are being made to remove these dyes by using number of physio‐chemical methods. Out of all the methods, adsorption technique is the most economical and efficient technique. For this purpose, efficient and cost‐effective adsorbents are needed. Neem leaf powder (NLP) containing Azadirachtin Indica, has been used for methylene blue (MB) dye removal. The interaction of dye on neem leaf containing Azadirachta indica plays an important role. Quantum mechanical calculations using density functional theory have been done in order to have an idea about interaction during adsorption. There is a possibility of both strong and weak interaction depending on the orientation of adsorbent and adsorbate.