Critical review on transition metal selenides/graphene composite as futuristic electrode material for high performance supercapacitors

Over time, there has been a significant increase in the need for energy due to the fast population expansion and industrialization. Unfortunately, the primary energy sources rely on burning fossil fuels, which harm the environment and contribute to climate change. Recent years have seen increased focus on the development of renewable energy sources like photovoltaic and wind energy with the goal of having zero carbon emissions by 2050. These renewable energy sources, however, are sporadic and not always accessible. In order to meet our everyday energy needs for a variety of applications, including wearable technology, there is a strong demand for the rapid development of energy storage devices. Supercapacitor (SC) technology has recently come to light as the most promising energy storage technology for upcoming renewable energy applications. In order to meet the energy requirements of wearable technology and electric cars, the scientist and researchers around the globe are now more interested than ever in fabrication of the most effective supercapacitors. Any supercapacitor's performance is influenced by a variety of elements, including the electrochemical characteristics of the electrode materials, the electrolyte, and the voltage range. A superior electrode material is one of these characteristics that is essential for enhancing the supercapacitor performance. The hunt for innovative electrode materials based on graphene is now receiving a lot of interest from the international scientific community working in the field of energy storage. Due to its exceptional qualities, including strong chemical stability, exceptional electrical conductivity, and great mechanical characteristics, graphene (Gr) is primarily being sought after as an electrode material for SCs. Additionally, the transition metal selenides (TMSs), which are attracting the attention of several researchers on a daily basis, are used as an electrode material for SC due to their various oxidation states. Due to the aforementioned considerations, we have chosen to highlight several TMS varieties in this review post. As an active electrode material in SCs, it is thought that TMSs and its composite with Gr will be crucial. These composites may store a huge amount of energy through pseudocapacitive and electrical double layer charge storage processes thanks to their varied oxidation states and vast surface area. The features of TMS and TMS/Gr based SC electrode materials, as well as current developments and problems, have been discussed in this current review paper.