posted on 2022-11-21, 19:46authored byBofang Shi, Hang Li, Xiaojie Fu, Chengcheng Zhao, Mingtao Li, Maochang Liu, Wei Yan, Honghui Yang
High energy consumption in pyrolyzing
precursors for
catalyst preparation
would limit the application of nitrogen-doped carbon-based single-atom
catalysts in actual pollutant remediation. Herein, we report an Fe
single atom (7.67 wt %) loaded polyaniline catalyst (Fe-PANI) prepared
via a simple impregnation process without pyrolysis. Both experimental
characterizations and density functional theory calculations demonstrated
that isolated −N group sites can fasten Fe atoms through
Fe–N coordination in PANI, leading to a high stability of Fe
atoms in a heterogeneous Fenton reaction. Highly dispersive yet dense
−N groups in PANI can be protonated to be adsorption
sites, which largely reduce the migration distance between reactive
radicals and organics. More significantly, frontier molecular orbitals
and spin-density distributions reveal that electrons can transfer
from reduction groups of PANI to an Fe(III) site to accelerate its
reduction. As a result, a remarkably boosted degradation behavior
of organics under near-neutral conditions (pH 6), with low H2O2 concentration, was achieved. This cost-effective Fe-PANI
catalyst with high catalytic activity, stability, and adsorption performance
has great potential for industrial-level wastewater treatment.