Gelatin-assisted co-exfoliation of graphene nanoplatelets/MoS2 for high-performance supercapacitors

Past decades have seen an enormous innovation with 2D layered materials especially related to their facile industrial-scale production and their applicability in the areas of clean energy and energy storage. Also, combining two different 2D layered materials offers exciting possibilities especially in attaining synergistic mechanical and electrical properties. The present study reports one-step liquid phase co-exfoliation of graphene (G) and MoS2 together i.e., graphene nanoplatelets (GNP)/MoS2 using high-temperature ultrasonication and gelatin. The co-exfoliated GNP/MoS2 reveals the presence of both GNP and MoS2 nanosheets together as authenticated by Raman and UV-vis spectroscopy. Further, transmission electron microscope (TEM) images also confirmed that both GNP and MoS2 were embedded together. As prepared GNP/MoS2 was then explored for supercapacitor application. GNP/MoS2 nanosheets showed a specific capacitance (C-s) value of 311.14 F g(-1) at 1 A g(-1) with excellent cycling stability (similar to 98.35% over 2000 cycles). Furthermore, an asymmetric supercapacitor device (ASC) was fabricated utilizing GNP/MoS2 and carbon black (CB). The fabricated device can operate in a wide potential window (0-1.8 V) showing a specific capacitance value of 80 F g(-1) and was used for lighting a commercial LED of similar to 1.8 V for up to 90 s. To the best of our knowledge, this is the first report on a new and facile synthesis pathway for producing high-quality co-exfoliated 2D nanosheets of MoS2 and graphene (G) hybrid which demonstrate superior supercapacitor performance.

Automated summary

The past decades have witnessed significant advancements in the innovation of 2D layered materials, particularly in the fields of clean energy and energy storage. This study presents a novel and facile synthesis pathway for high-quality co-exfoliated 2D nanosheets of MoS2 and graphene (G) hybrid, demonstrating superior performance in supercapacitors.