Noble-Metal-Free MIL-101(Cr)@rGO for Formaldehyde SERS Detection

The detection of volatile organic compounds (VOCs) is critical for ensuring food safety, particularly for identifying spoilage gases and food adulterants. Surface Enhanced Raman Spectroscopy (SERS) has traditionally relied on noble metals such as gold and silver for strong electromagnetic enhancement. However, these substrates present challenges in terms of cost, stability, and integration into real-world applications. In this study, we explore a hybrid metal–organic framework (MOF) with reduced graphene oxide (rGO) as a SERS active substrate. The developed material showed a good sensitivity for VOC formaldehyde (FA), easily detectable at peak 1452 cm−1and offering an RSD of 16.95%. Since the substrate did not rely on any noble metals for SERS enhancement, this low cost and easy material could be fine-tuned, creating alternative less-toxic materials for detection in industries such as food safety.