Metal–Organic Framework/Au Core/Shell Nanocubes for Spatially Aligned Molecular Analysis and Molecular-Fingerprint Sensing with Surface-Enhanced Raman Scattering

The spatial configuration of molecules on metal surfaces is a key parameter in reliably modulating the surface-enhanced Raman scattering (SERS) signals quantitatively, but the methods and platforms for controlling this configuration are not well established. Here, we utilized metal-organic frameworks (MOFs) to periodically and spatially arrange molecules in synthesizing zeolite imidazole framework-8 (ZIF-8)/Au core/shell nanocubes (ZACS NCs) for quantitative SERS. The uniform plasmonic Au nanoshell deposition onto ZIF-8 NCs was accomplished by the (100) facets of ZIF-8 and the use of cetyltrimethylammonium chloride (CTAC). In ZACS NCs, an interfacial Au/Zn alloy layer is between the AuNC core and ZIF-8 shell, which can modulate the plasmonic properties of the ZACS NCs. Single-particle Raman analysis suggests that characteristic vibrational Raman moieties of 2-methylimidazole (2-mIM) liga…