Graphene Quantum Dots (GQDs), zero-dimensional nanoparticles which are derived from carbon-based sources owned the new pavement for the energy storage applications. With the varying synthesis routes, the in-built properties of GQDs are enhanced in different categories like quantum efficiency, nominal size range, and irradiation wavelength which could be applied for the several of energy and optoelectronics applications. GQDs are especially applicable in the specific energy storage devices such as super capacitors, solar cells, and lithium-ion batteries which were demonstrated in this work. This paper critically reviews about the synthesis techniques used for the GQDs involving energy storage applications with increased capacitance, energy conversion, retention capability, and stability.

    Abstract
    1 Introduction
    2 Synthesis routes
        2.1 Top-down approach
        2.2 Comparison between top–down approaches
        2.3 Bottom–up approach
        2.4 Comparison between bottom–up approaches
    3 Energy-related applications of GQDs
        3.1 Capacitors
        3.2 Solar cells
    4 Conclusion
    References

• S. Akash Prabhu(Nanotechnology Division, Department of Electronic and Communication Engineering, Periyar Maniammai Institute of Science and Technology)
• V. Kavithayeni(Nanotechnology Division, Department of Electronic and Communication Engineering, Periyar Maniammai Institute of Science and Technology)
• R. Suganthy(Nanotechnology Division, Department of Electronic and Communication Engineering, Periyar Maniammai Institute of Science and Technology)
• K. Geetha(Nanotechnology Division, Department of Electronic and Communication Engineering, Periyar Maniammai Institute of Science and Technology)