**5. Conclusion**

MSCs as an energy storage devices attract considerable attention due to their notable characteristics such as smaller volume and high electrochemical performance. This chapter provides a brief overview of the recent developments in the field of 2D material-based all-solid-state MSCs. A brief note on the MSC device configuration and microfabrication methods for the microelectrodes has been illustrated. 2D materials based MSCs open up new avenues for the technologically relevant real-world applications. 2D materials such as MXenes, graphene, TMDs, and 2D metal–organic framework, TMOs/TMHs materials, have been described with regard to their electrochemical properties for MSCs. It is reported that the one issue faced by 2D materials is their unavoidable aggregation or restacking owing to their intense van der Waals interactions. To overcome this, there are approaches available like expansion of interlayer space with regard to enhanced storage ability or intercalation of guest molecules to increase the active sites. Moreover, for MSCs, 2D materials with vertical orientation grown on interdigitated current collectors is favorable to attain enhanced charge transport and low interfacial resistance. Additionally, to achieve higher conductivity and large specific surface area,

combining various materials with 2D hybrids is a practical approach to surpass each component material's challenges. Precisely, novel 2D materials with fascinating electrochemical properties are highly required. For example, 2D materials such as borophene, tellurene, silicene, phosphorene and germanene with higher electrical conductivity and enhanced specific surface area can be suitable candidates for highperformance MSCs. However, the coatings or surface functionalization of these 2D materials will be needed due to their chemical degradation and intrinsic surface instability under surrounding conditions. Above all, the processibility, reliability, and scalability of high-quality 2D materials are necessary not only for basic research but also for the real-world technological applications that need improved microfabrication methods such as screen printing and inkjet printing and 3D printing, *etc*.

Despite the recent advances in the design and fabrication of MSCs, MSC is still imperfect and require more developments. Some challenges limit practical implementation such as sustaining stable output voltage for wearable devices (microsystem and MSCs array just ignore these issues), current and output voltage are yet not pleased and more attempts should be assigned to design MSCs with a wider potential window. Moreover, various features, such as self-healing, hydrophobia, and stretchability, could be more developed to improve MSC performance. The device fabrication holds a significant role in technological innovation that, successively, affects the large scale production and the complexity of MSCs. It is expected that the integration of microdevices and smart functions into systems is unavoidable for facilitating the fast growth of smart electronic devices. MSCs based on 2D materials are focused on the powering of energy-consuming microdevices. Because of the complication in the smart systems' fabrication process, only limited works have been reported. So, innovative self-powered smart systems, including energy storage units, constitute a highly emerging research direction. Besides, the fabrication of a smart system with flexible, biodegradable and washable features can open the way for future independent, continuous, and intelligent daily electronics functioning. Moreover, these all-in-one self-powered systems can be used for health care applications in the future.
