Arrays of Triangular Au Nanoparticles with Self-Cleaning Capacity for High-Sensitivity Surface-Enhanced Raman Scattering

In the realm of surface-enhanced Raman scattering (SERS) research, the precise detection and effective cleansing of substances are critical. This study introduces a novel Au nanotriangle/Cs2AgBiBr6 (Au NT/CABB) SERS array, synthesized through a meticulous two-step process, which demonstrates remarkable SERS effectiveness. Using Rhodamine 6G (R6G) as the probe molecule, this substrate accurately detects target molecules and achieves an exceptional detection threshold of 1 × 10–13 M. The integration of CABB into the substrate endows it with photocatalytic properties, thereby accelerating the degradation of adsorbed signaling molecules and significantly enhancing the reusability of the Au NT/CABB arrays. Furthermore, the arrays exhibit outstanding SERS and photocatalytic performance with methylene blue (MB) and MB&R6G mixed solutions, distinguishing between the two signal molecules with high fidelity. Additionally, the SERS enhancement mechanism of the Au NT/CABB array is analyzed by the finite-difference time-domain (FDTD) simulation and energy band structure. These findings highlight the substrate’s dual capability in leveraging both electromagnetic and chemical enhancement mechanisms for superior SERS performance, complemented by an integrated photocatalytic self-cleaning feature, making it a promising candidate for environmental detection applications.