Iridium oxide (IrOx) is a promising implantable electrode material owing to its remarkable neural stimulation capacity. However, presently, IrOx electrodes lack biocompatibility and bioactive interactions with nerve tissues. Application of polymeric surface coatings results in a weak physical adhesion at the organic/inorganic interface, which limits their wide‐scale application. Herein, a smart iridium oxide‐plasma protein (IrOx‐PP) electrode with enhanced electroactivity, electrochemical stability, cytocompatibility, and bioactivity that can provide controllable topographical, electrical, and chemical stimuli to enhance neuronal activity is proposed. In the inorganic/organic nanoparticle (NP)‐protein corona structures, the soft NP‐corona led to repeated burst‐to‐zero‐to‐burst PP release, while the hard NP‐corona with an ordered atomic structure enhanced the electrochemical stability and bioactivity. The incorporated PP resulted in a higher current storage capacity, lower impedance, better cell growth, and significant neurite outgrowth compared with those obtained with pristine IrOx. The application of electrical stimulation to IrOx‐PP enabled simultaneous neuromodulation, on‐demand PP release, and cell uptake, with a 2‐fold higher cell density and significant neurite outgrowth on IrOx‐PP than on pristine IrOx. This bioactive inorganic‐organic hybrid electrode with the combined features of physical properties and improved neuromodulation is expected to be a revolutionary platform for efficient and biocompatible neural implantation.

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