Electrochemically nanotuned surface comprising 3D bimetallic dendrites fabricated on MWCNT for detection of 1,4-dioxane in water

•A 3D AuCu nanodendrites and multiwalled carbon nanotubes were employed to fabricate a nanosensor.•The bimetallic nanodendrites allows improved electron transfer for molecular sensing.•Novel surface was designed to detect toxicant, 1,4-dioxane in environmental water samples.•A very low detection limit of 3.27 ± 0.04 pM and a fast response time of 1.65 ± 0.05 sec is observed.