Synthesis of Multifunctional Plasmonic Nanodarts through One‐End Deposition on Gold Nanobipyramids for Tumor Organoid Ablation and Antimicrobial Applications

Abstract Plasmonic nanomaterials with multiple components and designed structures show diverse properties and functions owing to the synergistic effects of the different components. Engineering the compositional and structural complexity of plasmonic nanomaterials is a powerful technique for expanding their range of applications. A facile approach to an unprecedented dart‐like type of nanostructure with AgPd bimetal selectively deposited at one end of Au nanobipyramids, forming AgPd nanodarts, is reported here. The synthetic process involves both galvanic replacement and Ostwald ripening. The morphological evolution of the AgPd nanodarts is thoroughly investigated and the growth mechanism is put forward. The as‐obtained AgPd nanodarts exhibit an outstanding photothermal conversion efficiency and peroxidase activity, which make them powerful for photothermally–catalytically combined tumor organoid ablation. In addition, two types of AgPd nanodart‐derived single‐end nanostructures, AgPd@ZIF‐8, and AgPd@TiO 2 nanodarts, are prepared for the first time. The ZIF‐8 and TiO 2 shell are preferentially coated at the AgPd end of the AgPd nanodarts, respectively. Both AgPd@ZIF‐8 and AgPd@TiO 2 nanodarts show superior antimicrobial activities. The protocol and concept of modulating the structure of the nanodarts in this work can be extended to the development of a new class of plasmonic nanostructures with multifunctionalities.