<p>In this work, spongy-carbon nanotubes were utilized as redox material to enhance the capacitance of graphene-based supercapacitors. Such carbon nanotubes had average diameters of 570&#xa0;nm and were entangled forming a porous network. Firstly, supercapacitors were constructed only with graphene electrodes and had a capacitance and energy density of 322.12&#xa0;F g⁻¹ and 44.73 Wh kg⁻¹, respectively. In contrast, supercapacitors made with electrodes containing Carbon nanotubes had a higher capacitance: 500.16&#xa0;F g⁻¹ and energy density: 69.46 Wh kg⁻¹ (at room temperature). Thus, the capacitance was enhanced by 55% after introducing the spongy-Carbon nanotubes on the supercapacitor electrodes. Raman analysis and X-ray photoelectron spectroscopy measurements were carried out on the supercapacitor-electrodes and found the presence of oxygen groups and oxygen vacancies defects, which worked as redox centers for the charge storage. Furthermore, the devices made with spongy-carbon nanotubes presented high electrochemical stability because their capacitance retention was above 90% after 1000 cycles of charge–discharge. The supercapacitors were also operated at a low temperature of 2&#xa0;°C (scarcely reported in the literature) and produced a capacitance and energy density of 432.35&#xa0;F g⁻¹ and 60.04 Wh kg⁻¹, respectively. Interestingly, the maximum output voltage of 0.32&#xa0;V was obtained in the devices operating at 2&#xa0;°C. Later, the supercapacitor-electrodes made with spongy-carbon nanotubes were recovered and utilized to remove cooking-oil and polystyrene microplastics from contaminated tap water with maximum adsorption capacity of 11.5&#xa0;g g⁻¹ and 1.2&#xa0;g g⁻¹, respectively. Overall, this investigation demonstrated the reuse of SC-electrodes for the elimination of emerging pollutants, which extended the lifetime of spongy-carbon nanotubes and promoted their sustainability.</p> Graphical Abstract <p></p>