Enhancing Interfacial Charge Transport in Gold Nanoparticle@Polyaniline Hybrids via N ‐Heterocyclic Carbene Linkers

ABSTRACT N ‐Heterocyclic carbenes (NHCs) have emerged as a unique class of ligands for gold nanoparticles (Au NPs), combining strong metal binding with intrinsic electronic conductivity. Yet over the past decade, studies on Au NP@NHC systems have primarily focused on their stability, while the conductivity of NHCs has remained largely unexplored due to synthesis challenges. Here, we present a synthetic strategy that addresses this gap by employing amino‐functionalized NHC‐Au complexes with in situ oxidative polymerization of polyaniline (PANI) to yield electronically coupled Au NP@NHC‐PANI hybrids in aqueous media. This strategy enables both a controlled PANI shell growth and introduction of an electronically active NHC interlayer. Single‐particle scattering spectroscopy reveals that NHCs improve the interfacial electronic coupling as evidenced by pronounced plasmonic linewidth broadening. Conductivity measurements further confirm that NHCs enhance charge transport: conductive atomic force microscopy (C‐AFM) shows an increase in contact current from 14.6 to 99.4 pA under a 300‐mV bias, while lateral four‐probe conductance increases from 0.17 to 3.5 nS. These results provide the first direct experimental evidence of the conductive role of NHCs in hybrid NP‐polymer systems, establishing a new interface‐engineering strategy for the rational design of electronically delocalized nanostructures and their applications in nanoelectronics.