Preparation of dopamine polymer-modified Ni foam packing: Coating process, mass transfer, and DFT calculation studies

The coating stability of dopamine-polymer-modified Ni foam is important for its application in micropacked bed reactors. In this study, hydrophilically modified polydopamine (PDA)/Ni foam and polylevodopa (PLD)/Ni foam, and hydrophobically modified F₉-PDA/Ni foam and F₉-PLD/Ni foam were prepared. The hydrophobically modified Ni foam packings had a gas-liquid mass transfer enhancement performance in micropacked bed reactors. Based on the gas-liquid flushing experiment results, the stability of PDA/Ni foam and F₉-PDA/Ni foam was better than that of PLD/Ni foam and F₉-PLD/Ni foam. PFHS can interact with PDA and PLD to produce hydrogen bonds and chemical reactions. The adsorption of PFHS on PLD was more stable, and the chemical reaction was more spontaneous. The experiment and DFT calculation confirmed the binding strength of PDA/PLD and Ni foam acts as a key controlling factor for the overall stability of F₉-PDA/PLD-Ni foam. As a result, the adhesion of PDA on the Ni foam was significantly better than that of PLD.