Hierarchical One-Dimensional Ammonium Nickel Phosphate Microrods for High-Performance Pseudocapacitors

Abstract

High-performance electrochemical capacitors will drive the next-generation portable, flexible and wearable electronics. Unlike the conventional all-carbon supercapacitors (electric double layer capacitors, EDLC) with high power but poor energy density, pseudocapacitors capitalize the high energy density inherent to reversible redox reactions and provide a facile means to enhancing the energy ratings of supercapacitors. The high length-to-diameter ratio and anisotropic character of 1-D architecture makes them suitable for use in energy storage. For the first time, we report 1-D microrod structures (~ 36 nm width) of ammonium nickel phosphate hydrate (ANPmr) as a pseudocapacitor with high energy rating and power handling. To confirm the data, the ANPmr-based pseudocapacitor was subjected to various configurations (i.e., half-cell, symmetric, asymmetric, and flexible all-solid-state) and in each case it gave excellent values compared to any accessible literature to date. We clearly demonstrate that a flexible all-solid-state ANPmr-based pseudocapacitor achieved high areal capacitance of 66 mF cm−2 with extra-ordinary energy (21.2 mWh cm−2) and power (12.7 mW cm−2) densities. This work opens doors for a facile, robust and scalable preparation strategy for low-cost, earth-abundant electrode materials for high-performance pseudocapacitors.

α‐MnO2‐Sensitized SrCO3−Sr(OH)2 Supported on Two‐Dimensional Carbon Composites as Stable Electrode Material for Asymmetric Supercapacitor and Oxygen Evolution Catalysis

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A Flexible Aqueous Asymmetric Lithium‐Ion Supercapacitor with High Voltage and Superior Safety

“…CV and GCD of the as‐assembled supercapacitor were measured by a CHI 660E potentiostat. Capacitance of a supercapacitor ( C ) was calculated according to the formula where I is the current (A), Δ t is the discharge time (s), and Δ U is the operating discharge potential range (V). The specific capacitance C sp (F/g) of the asymmetric supercapacitor was calculated from where m (g) is the total mass of Mn 5 O 9 and FeOOH.…”

A Review on Synthesis and Characterization of Activated Carbon from Natural Fibers for Supercapacitor Application

“…Hence, the capacitance of a supercapacitor can be illustrated as shown in Equation 1. Capacitance (C) is defined as the ratio of stored charge(Δq) to change in potential (ΔV) (Raju & Ozoemena, 2015).…”