environmentally friendly energy storage devices. As an emerging energy powering sources, supercapacitors (SCs) hold a vital and individual position owing to their high power density, excellent cycling stability, fast charge/discharge process as well as noticeable reliability, tremendously bridging the gap between rechargeable batteries and traditional capacitors in terms of energy density and power density. [1][2][3][4] Nevertheless, their commercial applications are still seriously impeded since energy densities of SCs are far lagging behind rechargeable batteries. [5,6] In the light of the critical parameters that decide the energy density (E = 1/2CV 2 ) of supercapacitor devices, [7][8][9] substantial efforts have been dedicated to maximizing the energy density via elevating the overall cell voltage (V) and total specific capacitance (C) governed by negative and positive electrodes. Configuration of asymmetric supercapacitors (ASCs) has emerged as a desirable strategy because of the expanded V arised from the absolutely opposite potential window of the two dissimilar electrode materials. [10][11][12] Accordingly, considerable research interest has been invested in constructing highly capacitive negative and positive electrode materials.Until now, transition metal oxides, hydroxides, or phosphides, especially Ni-Co compounds with low cost, natural abundance, and environmentally benign, are mostly employed as positive electrode materials in ASCs because they can present variable oxidation states, favorable electrochemical activity, and large theoretical-specific capacitance based on redox reactions, so they have received extensive attentions as perfect candidates in ASCs. [13][14][15][16][17][18] However, in comparison of the extraordinary advancement obtained by positive electrode materials, the lack of desired negative electrodes restricts the progress of high-performance ASCs. Previously, carbonaceous materials are still the most widely used as negative electrode, giving rise to low-specific capacitance of 100-250 F g −1 . [19][20][21][22][23] In this regard, pseudocapacitive negative electrode materials are proposed to be hopeful alternatives, whereas the restricted studies and poor , even when charging the device within 6.5 s, the energy density can still maintain as high as 45 W h kg −1 at 26.1 kW kg −1 , and the ASC manifests long cycling lifespan with 86.6% capacitance retention even after 5000 cycles. This pioneering work not only offers an attractive strategy for rational construction of high-performance SiC NW-based nanostructured electrodes materials, but also provides a fresh route for manufacturing next-generation high-energy storage and conversion systems.