[Young-Woo Pyo/ Prof. Hong-Gyu Park] Self-organized nanoplasmonic artificial leaf for hot-carrier bioelectronic interfaces (published in Nature Photonics)

Without discrete pixels or wired leads, natural plant leaves respond to light and relay electrochemical signals to surrounding tissues through nanoscale chlorophyll-containing protein complexes - an elegant capability sought in next-generation leadless optoelectronic systems. Although semiconductors and their heterojunctions are commonly employed to mimic photosynthesis, nanoplasmonic structures offer a largely untapped alternative. Harnessing plasmonic hot carriers for macroscopic systems remains challenging, limiting applications in tissue-level neuromodulation and human-machine interfaces. We introduce a hot-carrier artificial leaf optoelectronic device, formed by thermally self-organized 3D gold–titanium dioxide units on ultrathin membranes. These nanoplasmonic interfaces enhance visible-light optoelectronic responsiveness at sub-100-nm thickness, support highly localized hot-carrier injection, and exhibit stable, linear performance over a wide range of light intensities, overcoming the material, bandgap, and carrier diffusion limits of conventional semiconductors. The resulting nanoplasmonic devices enable leadless, multimodal optoelectronic modulation and pixel-less optical pattern recognition, presenting a potentially scalable platform for hot carrier-enabled biomedical, nanophotonic, and human-machine interface technologies.

