Flexible Solid PANI Fiber Networks/Ni‐MOF@CC Electrodes for High‐Performance Capacitors: Synthesis and Stability Study

Abstract

In this work, the nickel‐based metal organic framework (Ni‐MOF) is attached to the conductive carbon cloth (CC) by using a hydrothermal reaction. In order to make MOFs strongly interacted with CC, polymeric molecules of polyaniline (PANI) are deposited on Ni‐MOF@CC employing an in–situ polymerization method. The PANI shows a three‐dimensional fiber‐network morphology. Due to the improved electrical conductivity and the porous networks, the electrochemistry property of the obtained flexible PANI/Ni‐MOF@CC is greatly enhanced compared with Ni‐MOF@CC. The specific capacitance of PANI/Ni‐MOF@CC reaches 109 F cm−2 (573 F g−1). The optimum energy density of PANI/Ni‐MOF@CC at 0.1 A cm−2 can be 7 mWh cm−2 with power density of 70 mW cm−2. Because the fiber networks of PANI on MOF enhances the interactions between MOF and CC, the PANI/Ni‐MOF@CC shows high stability of 95 % capacitance retention after 5000 charge‐discharge cycling.

Porous Fiber Processing and Manufacturing for Energy Storage Applications

“…Porous materials including nanoporous fibers have found various applications. One of the most important applications is for energy storage devices for example, capacitors [117][118][119][120][121][122][123][124][125][126][127][128][129][130][131] and rechargeable batteries [132][133][134][135][136][137]. Another important branch of applications is environment protection related.…”

Scalable Construction of Flexible Composite Textile Electrodes through In Situ Growth of Polyaniline Nanofibers on Carbon Cloths under Electric Field toward High Areal Capacitance Supercapacitors

“…Currently, electronic fabrics with flexibility, portability, and high capacity of energy storage and conversion exhibit great potential in the field of wearable technology. − Commercial carbon cloth has widely served as low-cost and lightweight supports and current collectors due to their special porous network structure, high mechanical flexibility and stability, and easy modification. , However, their applications as free-standing electrodes were greatly limited due to relatively low surface area and weak storage capacity. The design and construction of a composite textile electrode especially with high areal energy density have been widely explored by growing or coating pseudocapacitive materials such as polyaniline (PANi) with high theoretical specific capacitance on carbon cloth. ,,, Furthermore, to fully implement wearable electronics, high areal capacitance of flexible supercapacitors is given importance more than the gravimetric one. − Generally, a great number of pseudocapacitive materials are loaded onto the surface of a textile to achieve high areal capacitance and rate capability as well as cycling stability, but when a PANi particle or film is excessively introduced, the electrode materials do not exhibit remarkable electrochemical behaviors as expected. − Fortunately, superior electrochemical performance can be achieved by growing PANi nanofiber arrays onto the surface of carbon cloth that can provide a high specific surface area, an efficient electron transport path, optimized ion-diffusion channel, and slight volume change .…”

“…1−5 Commercial carbon cloth has widely served as low-cost and lightweight supports and current collectors due to their special porous network structure, high mechanical flexibility and stability, and easy modification. 6,7 However, their applications as freestanding electrodes were greatly limited due to relatively low surface area and weak storage capacity. The design and construction of a composite textile electrode especially with high areal energy density have been widely explored by growing or coating pseudocapacitive materials such as polyaniline (PANi) with high theoretical specific capacitance on carbon cloth.…”