Revolutionizing Micro‐Scale Energy Storage by 0D Carbon Nanostructures: Synthesis, Integration, Performance Optimization Mechanisms and Sustainable Applications

Abstract The micro‐scale energy storage devices (MESDs) have experienced significant revolutions driven by developments in micro‐supercapacitors (MSCs) and micro‐batteries (MBs). This review summarizes the advancements of MSC and MB architecture, highlighting the electrode–electrolyte designs and the emergence of alkali metal ions aqueous batteries. The performance and synthesis of carbon quantum dots (CQDs), graphene quantum dots (GQDs), and their synergistic effects for energy storage applications are investigated. The focus is on integrating CQDs/GQDs into the MESDs for enhanced performance. The development of compositing CQD/GQD with other materials, reveals their capacitive and pseudocapacitive performance, extending the MESDs’ possibilities. Moreover, this review systematically covers various fabrication techniques from photolithography to printing techniques. The merits and practicality of each technique for fabricating MSCs and MBs are assessed. Electrochemical performance evaluation, capacitance enhancement, charge–discharge kinetics, and stability assessments are presented to demonstrate the efficiency of MESDs with practical applications. Despite significant progress, challenges remain, particularly in the scalability of fabrication and understanding long‐term stability. Nevertheless, the prospects are promising, with avenues in synthesis, fabrication, and electrochemical performance evaluation, which lead to a paradigm shift in MESDs. This review offers a broad perspective, combining innovations across diverse domains and directing the frontline of microelectronics.