CNTs induced irregular 2D nanosheet SnS composites as active materials of electrodes for capacitive deionization

Abstract

Tin disulfide/carbon nanotubes (SnS/CNTs) composites have been prepared through a solvothermal method with the purpose of being used as active materials of electrodes for capacitive deionization (CDI). SnS/CNTs composites with different CNTs content (0, 5, 10, 15, and 20 wt.%) were prepared and analyzed through X-ray diffraction, scanning electron microscopy, and nitrogen adsorption and desorption measurement. Results revealed that the role of CNTs added during the synthetic reactions was more than a network facilitating the distribution of SnS, but also a kind of matter inducing a change in the morphology and pore structure of SnS during its crystallization. Compared with a cluster-like morphology of pure SnS, an irregular 2D nanosheet SnS was observed in SnS/ CNTs composites, especially for SnS/CNTs-10% composite. This composite exhibited an enlarged specific surface area and a more homogeneous distribution of mesopores. Furthermore, a relatively high specific capacitance of 68.1 F/g and low resistance were verified for SnS/CNTs-10% composite. Results of desalination performance demonstrated that SnS/CNTs-10% composite electrode showed a favorable desalination capacity of 7.83 mg/g. The introduction of CNTs during SnS preparation generated a novel 2D nanosheet structure of SnS which improved the desalination performance and could be a potential material for CDI electrodes.