Fabrication of dual functional 3D-CeVO4/MWNT hybrid nanocomposite as a high-performance electrode material for supercapacitor and L-Tryptophan detection

•3D interconnected CeVO4/MWNT hybrid nanocomposite (HNC) are prepared through a simple ultrasonication method.•3D-CeVO4/MWNT HNC is applied for both energy storage and sensor application.•It exhibited a high specific capacity of 378 C g−1 at 1 Ag−1.•3D-CeVO4/MWNT HNC displays a very low limit of detection of 0.07 μM for the detection of L-Tryptophan and also applied for real sample monitoring. The development of a novel material with excellent properties for energy storage and sensors has been considered the best material to overcome the future energy demand and economic crisis. Herein, a three-dimensional (3D) hybrid nanocomposite (3D-CeVO4/MWNT HNC) was fabricated based on; i) synthesis of cerium vanadate nanoparticles (CeVO4 NPs) through simple precipitation, and ii) successful inclusion of CeVO4 NPs on multiwall carbon nanotube (MWNT) by using ultrasonication approach. To reveal the physicochemical parameters of 3D-CeVO4/MWNT HNC, X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), powder X-ray diffraction (P-XRD), field emission-scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), and electrochemical techniques are utilized. As synthesized 3D-HNC possessed the specific features of both CeVO4 NPs and MWNT exhibits high electrocatalytic behavior due to its high surface area and conductivity. It has been more attractive for the application of energy storage and as an electrochemical sensor. 3D-CeVO4/MWNT HNC reveals high specific capacity value of 378 C g−1 at 1 A g−1 with long cycle life with 90.8% retention. Also, the proposed sensor shows a low detection limit of 0.07 μM and sensitivity of 20.71 µA µM−1 cm−2 with a dynamic linear range of 2-322.5 μM. Then the resulting sensor was also applied to detect the L-Trp in the real-time sample. Hence 3D-CeVO4/MWNT HNC could be a promising material for both applications of the electrochemical sensor and supercapacitor. [Display omitted]