Deep eutectic solvents-mediated synthesis of barium stannate/halloysite nanotubes-based nanocomposite for electrochemical detection of hazardous 4-nitroaniline

4-Nitroaniline (4-NA) compounds are considered highly hazardous to the environment and can be found in various chemical products, including pigments, dyes, fungicides, and pesticides. The presence of 4-NA in water poses significant carcinogenic risks to humans. Therefore, there is an urgent need to monitor and detect the environmentally hazardous 4-NA, especially in water samples. In this study, we have developed a novel nanocomposite based on barium stannate/halloysite-based (BaSnO₃/HNTs) with a nanotube structure. The nanocomposite was synthesized using natural deep eutectic solvents (NADESs) and aimed at the selective electrochemical detection of 4-NA in water samples. Morphological studies clearly revealed the random incorporation of BaSnO₃ nanoparticles (NPs) with diameters ranging from ∼10–50 nm onto the surface of HNTs. The incorporation of BaSnO₃ NPs created more active sites and facilitated fast electron transport, as confirmed by EIS. Under a saturated N₂ condition and at pH 7.0, the BaSnO₃/HNT/SPCE exhibited excellent electrochemical performance with a very low limit of detection and a wide linear range of 2 nM and 0.009–1126 μM, respectively. Additionally, the proposed sensor for 4-NA demonstrated good anti-interference ability, repeatability (RSD ∼1.31%), and stability (RSD ∼1.09%). The obtained electrochemical analytical results of the synthesized composite validate its superior potential for real-time applications.