Progress of Nanostructured Electrode Materials for Supercapacitors

Abstract Supercapacitors, as a type of energy storage system, bridge the power/energy gap between conventional capacitors and batteries due to attractive properties such as high power density, long cycle lifespan, and large temperature range. However, the low energy density of supercapacitors compared to lithium‐ion batteries has hindered their general application. In general, the electrochemical performance of supercapacitors is closely related to the structure of their electrode materials, electrolytes, and device design. The main materials used in electrochemical double‐layer capacitors (EDLCs) are carbon materials with various architectures. This is due to their high surface area, good electric conductivity, and intrinsic stability. In this review, recently reported carbon‐based nanostructured electrode materials with 0D, 1D, 2D, and 3D structures are systematically reviewed. The effect of nanostructuring on the properties of supercapacitors including specific capacitance, rate capability, and cycle stability is explored, the details of which may serve as a guide to electrode design for the next generation of EDLCs.