Trends and frontiers in graphene-based (bio)sensors for pesticides electroanalysis

Undoubtedly, carbonaceous (nano)materials are the most widely used feedstock to obtain improvements in electrochemical devices, but graphene has attracted strong scientific and technological interest due to its exceptional physicochemical properties. Graphene-sheets functionalization, integration with metallic nanoparticles, organic and inorganic molecules and/or groups, synthesis method, and chemical or thermal reduction of graphite oxide can greatly influence the performance of the devices. In general, graphene-based (bio)sensors overcome the conventional ones in terms of sensitivity, electrocatalytic activity, potential window, and charge-transfer processes. They can be a key tool for the miniaturization and development of fast, sensitive, versatile, environment-friendly, and in situ electroanalytical methods for pesticides, in particular for carbamates, organophosphates, organochlorines, benzimidazole, and neonicotinoids, among others. The constant advances in the application of these devices are unquestionable, but there are still questions about the interfacial redox phenomena that are not fully understood and deserve to be investigated. This chapter describes the exciting progress and challenges in this field, emphasizing the main scientific findings.