This study investigates the development of electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) mats loaded with graphene oxide (GO) and carbon nanotubes (CNTs) for water treatment and sensing applications. The mats were designed to adsorb methylene blue (MB), a common dye pollutant, while also detecting the dye concentration. The results show that increasing the GO content enhances sorption capacity, which is beneficial for wettability and active area. The equilibrium adsorption is well predicted by the Langmuir isotherm model, with maximum capacities ranging from 120 to 555 mg/g. The structural and electrical properties of the materials were studied as a function of MB adsorption, revealing that MB molecules increase the electrical conductivity of the samples in a dose-dependent manner. Mats containing only CNTs, despite having the worst sorption performance, exhibited the highest electrical performance and showed interesting changes in electrical response as a function of the adsorbed dye amount, with a linear response and high sensitivity (309.4 μS cm\(^{-1}\) mg\(^{-1}\)) in the range of 0–235 μg of dye adsorbed. The study highlights the potential of these materials for monitoring small amounts of MB in contaminated water and transforming waste sorbents into high-value products, such as flexible sensors for detecting low pressure and human motion.This study investigates the development of electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) mats loaded with graphene oxide (GO) and carbon nanotubes (CNTs) for water treatment and sensing applications. The mats were designed to adsorb methylene blue (MB), a common dye pollutant, while also detecting the dye concentration. The results show that increasing the GO content enhances sorption capacity, which is beneficial for wettability and active area. The equilibrium adsorption is well predicted by the Langmuir isotherm model, with maximum capacities ranging from 120 to 555 mg/g. The structural and electrical properties of the materials were studied as a function of MB adsorption, revealing that MB molecules increase the electrical conductivity of the samples in a dose-dependent manner. Mats containing only CNTs, despite having the worst sorption performance, exhibited the highest electrical performance and showed interesting changes in electrical response as a function of the adsorbed dye amount, with a linear response and high sensitivity (309.4 μS cm\(^{-1}\) mg\(^{-1}\)) in the range of 0–235 μg of dye adsorbed. The study highlights the potential of these materials for monitoring small amounts of MB in contaminated water and transforming waste sorbents into high-value products, such as flexible sensors for detecting low pressure and human motion.