Dubal, D.Abdel-Azeim, S.Chodankar, N.Han, Y.2020-03-052020-03-052019iScience, 2019; 16:50-622589-00422589-0042http://hdl.handle.net/2440/123531Pseudocapacitors hold great promise to provide high energy-storing capacity; however, their capacitances are still far below their theoretical values and they deliver much lower power than the traditional electric double-layer capacitors due to poor ionic accessibility. Here, we have engineered MoN nanoparticles as pseudocapacitive material on phosphorus-incorporated carbon fabric with enhanced ionic affinity and thermodynamic stability. This nanocomposite boosts surface redox kinetics, leading to pseudocapacitance of 400 mF/cm² (2-fold higher than that of molybdenum nitride-based electrodes) with rapid charge-discharge rates. Density functional theory simulations are used to explain the origin of the good performance of MoN@P-CF in proton-based aqueous electrolytes. Finally, an all-pseudocapacitive solid-state asymmetric cell was assembled using MoN@P-CF and RuO₂ (RuO₂@CF) as negative and positive electrodes, respectively, which delivered good energy density with low relaxation time constant (τ₀) of 13 ms (significantly lower than that of carbon-based supercapacitors).en© 2019 The Author(s). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).Materials ScienceJournal article003011742810.1016/j.isci.2019.05.0180004733217000052-s2.0-85066324037475477