Recent Progress in Photocatalytic Self-Cleaning Surface-Enhanced Raman Spectroscopy Substrates for the Recyclable Detection of Food Contaminants

Surface-enhanced Raman spectroscopy (SERS) is an emerging ultrasensitive analytical technology with potential applications in many fields, such as food safety detection, environmental monitoring and clinical diagnosis. However, traditional SERS detection mainly relies on Au or Ag nanomaterials as substrates, resulting in poor signal uniformity, poor stability and high cost. Benefitting from the combination of SERS and photocatalysis, the signal uniformity, batchto-batch consistency and cost effectiveness can be significantly improved by using semiconductor-noble metal composite nanomaterials as SERS substrates. Moreover, the elimination of hazardous analytes and the recyclable SERS detection can be achieved via photocatalyzed degradation. The current review mainly focuses on new developments in photocatalysis-SERS for the recyclable detection of food contaminants. The design and fabrication procedures of recyclable SERS substrates made of inorganic/organic semiconductor photocatalysts and noble metal nanomaterial composites are introduced along with their advantages and shortcomings, and their potential applications in the detection and elimination of typical food contaminants including pesticides, banned additives and antibiotics are discussed in detail. Finally, the current challenges and future trends in this field are also summarized.