Advanced Heterostructured PEDOT-PB Transducer Interface via One-Step Progressive Electrochemical Deposition for Stable and High-Performance Hydrogen Peroxide Electrocatalysis.

Heterostructured organic-inorganic composites with syngenetic properties are highly appealing as advanced material interfaces for emerging electronic and bioelectronic device applications. For decades, Prussian blue (PB) has attracted tremendous attention due to its excellent and unique electrocatalytic properties as transducer materials, while conventional inorganic PB lacks sufficient stability and conductivity for advancing performance. Here, we demonstrate an innovative one-step progressive electrochemical deposition approach for the facile fabrication of heterostructured Poly(3,4-ethylenedioxythiophene) (PEDOT)-PB ( PEDOT-PB) transducer interface with excellent stability and electrocatalytic performance. The PEDOT-PB was prepared by the simultaneous potentiodynamic oxidation of Fe(II) precursors and electropolymerization of EDOT monomers, forming a porous and heterostructured PEDOT-PB interface with embedded PB nanoparticles. The PEDOT-PB possessed 16.6- and 11.8-fold higher surface concentration (Γ) of PB, delivered excellent cycling stability (96.7% after 50 scanning cycles), enhanced electrode kinetics characterized by the lowest (0.57 Ω), and the highest catalytic rate constant () of 1238 M s toward hydrogen peroxide (HO) reduction compared with unary PB and stepwise PEDOT-PB. Moreover, the PEDOT-PB showed good electrocatalytic stability for HO reduction in a static system (3000 s) and a flow injection system (100 measurement cycles), retaining 80.7% and 96.6% of its initial catalytic performance, respectively. Our development provides a facile route for the design and preparation of high-performance, stable, and heterostructured PEDOT-PB for advanced electrochemical transducers for sensors and biosensors, electrocatalysis, and biofuel cell applications.