Bioinspired Neuron-like Adsorptive Networks for Heavy Metal Capture and Tunable Electrochemically Mediated Recovery.

Abstract

Electrochemical techniques have garnered increasing attention as a heavy metal remediation platform for pollutant mitigation and sustainable recycling. Inspired by the biological signal-transfer mode, biomimic neuron-like hierarchical adsorptive networks were constructed by interweaving one-dimensional manganese oxide nanowires into polyaniline-decorated hollow structural metal-organic frameworks (MOFs). The prepared biomimic neuron adsorbent exhibits good adsorption capacity toward cations (Pb2+) and oxyanions (Cr2O72-) at the neutral state; tunable cation/oxyanion desorption can be electrochemically switched at the oxidized and reduced states, respectively, where the biomimic neuron-like hierarchical adsorptive networks facilitated electron transfer and benefited substantial redox reactions. The combination of simulations and calculations demonstrates that the curvature-induced polarization in a hollow MOF structure enhances the desorption efficiencies by improving the redox processes at the electrode-electrolyte interface, which facilitate the promising implementation in terms of water economy and downstream waste sustainability.