Nanopore Confinement Effect Mediated Heterogeneous Plasmonic Metasurfaces for Multifunctional Biosensing Interfaces

Plasmonic metasurfaces (PMs) exhibit extraordinary optical response due to surface lattice resonance, which is crucial for realizing high-performance photovoltaic device preparation. In this work, a nanopore confinement effect-mediated MOF@UsAu is proposed as a novel PM heterojunction for photovoltaic interfaces. 2D MOFs have the unique advantage of a tunable and ordered porous structure. Its nanopore confinement effect regulates in situ synthesis of AuNPs on the MOF surface in dimensions and regions. The interface delocalization induced by work function matching and the Schottky barrier formed by band bending enhance the ordered LSPR and photovoltaic response of PM heterojunctions, achieving a significant enhancement of SPR interface plasma electric field. Based on the bi-directional interaction design between the S-shaped multifunctional peptide and MOF@UsAu, a PMs-enhanced SPR biosensor is constructed for direct, real-time, and ultrasensitive analysis of tumor exosomes. This study is the first to use 2D MOFs as substrates for constructing PMs and designing customized in situ synthesis strategies for specific application scenarios. It provides new ideas for the design of novel PMs and the construction of customized photovoltaic interfaces, expected to be extended to various types of photovoltaic device applications.