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Cost-Effective Strategy for Surface Modification via Complexation of Disassembled Polydopamine with Fe(III) Ions
journal contribution
posted on 2019-02-23, 00:00 authored by Peibin Zhang, Wenjihao Hu, Min Wu, Lu Gong, Anqi Tang, Li Xiang, Baoku Zhu, Liping Zhu, Hongbo ZengMussel-inspired polydopamine
(PDA) deposition provides a prominent
approach for constructing functional coatings, which has received
much research interest over the past decade. However, large PDA aggregates
often formed and precipitated from the solution during the deposition
process, significantly lowering the utilization efficiency of dopamine
for surface modification. It is of both fundamental and practical
importance to “reactivate” and reuse the precipitated
aggregates to achieve higher usage efficiency of PDA in surface modifications.
In this work, we report a facile, substrate-independent, and cost-effective
coating strategy, by disassembling the precipitated PDA aggregates,
to achieve the coating deposition through the complexation of disassembled
polydopamine (d-PDA) species with Fe(III) ions on various substrates.
Adsorption tests determined by a quartz crystal microbalance with
dissipation (QCM-D) monitoring technique indicated that the pH of
the solution and the ratio of d-PDA to Fe(III) significantly influence
the deposition behavior of d-PDA/Fe(III). Force measurements using
a surface force apparatus demonstrated that the coordination interaction
between d-PDA and Fe(III) was the major force leading to the formation
of coatings. The deposited d-PDA/Fe(III) coatings featured controllable
nanoscale thickness, uniform surface morphologies, and light color.
Furthermore, the d-PDA/Fe(III) coating could act as an intermediate
layer in the preparation of hydrophobic polyurethane sponge for highly
efficient oil/water separation. This work provides a useful strategy
to realize the reusability of PDA aggregates for versatile surface
functionalization, with implications for the fundamental understanding
of the formation mechanism in the metal–phenolic complexation
systems and development of new coating approaches in various engineering
applications.