Self-Assemble Strategy to Fabricate High Polyaniline Loading Nanocarbon Hydrogels for Flexible All-Solid-State Supercapacitors

Abstract

Polyaniline and nanocarbon composite hydrogels (PCR) are fabricated by a self-assemble strategy with polyaniline content as high as 66.7%, where multiwall carbon nanotubes (MWCNTs) as reinforcing bars are embedded into the three-dimensional graphene skeletons to enhance the conductivity and mechanical stability. After the incorporation of MWCNTs, the conductivity, porous volume, and specific surface area of the PCR hydrogel increase 32, 53, and 36.8% with respect to the PR hydrogel, respectively. First-principles density functional theory calculations show that the interactions between PANI and graphene/GO are all adsorptive, thereby producing a much more homogeneous and compact structure. Due to this favorable structure, the stress and mechanical degradations of PANI can be alleviated during the repeated charge/discharges. As such, the as-prepared hydrogel-based supercapacitor electrode shows a very high specific capacitance about 917 F g–1 at 1 A g–1 and relatively high rate capability of about 84% from 1 to 20 A g–1. The assembled flexible asymmetric all-solid-state supercapacitor achieves a high energy density of about 31.32 W h kg–1 at the power density (364.93 W kg–1). These results demonstrate that polyaniline and nanocarbon composite hydrogels have great potential to become an advanced power device for wearable electronics.

Flexible and Wearable Zinc-Ion Hybrid Supercapacitor Based on Double-Crosslinked Hydrogel for Self-Powered Sensor Application

“…At a current density of 1.0 mA cm −2 , the discharge capacitance of the ZHS device is as high as 1.364 F cm −2 , while the capacitance remained at 1.244 F cm −2 when the current density was further increased to 2.0 mA cm −2 . The calculated energy density for the ZHS device was 242 Wh kg −1 at a power density of 228 W kg −1 , i.e., superior to those of other sandwich-structure supercapacitors ( Figure 3 d) [ 25 , 26 , 33 , 34 , 35 , 36 , 37 , 38 , 39 ]. The cyclic stability test of the ZHS ( Figure S6 ) showed 90% retention after 1000 cycles, indicating stable charge–discharge performance.…”

“…( d ) Comparison of energy density and power density among reported cutting-edge supercapacitors. (Yang, 2020 [ 25 ]; Liu, 2021 [ 26 ]; Chen, 2019 [ 33 ]; Zhang, 2021 [ 34 ]; Ding, 2021 [ 35 ]; Sandhiya, 2020 [ 36 ]; Khazaeli, 2020 [ 37 ]; Li, 2020 [ 38 ]; Sun, 2018 [ 39 ]) ( e ) Ragone plots of the ZHSs with the hydrogel prepared with different Zn 2+ concentrations. ( f ) Discharge capacitance of ZHS at different temperatures.…”

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

“…Two pairs of redox peaks (A1/C1 and A2/C2) appeared in the CV curves at a scan rate of 5 mV s –1 for the electrodes obtained at various aniline concentrations, as displayed in Figure a, indicating their pseudocapacitive characteristics. More clearly, the A1/C1 and A2/C2 peaks were assigned to the transition between leucoemeraldine and emeraldine salt as well as the emeraldine–pernigraniline transformation of PANi, respectively. ,− Furthermore, the maximum current density was observed for the electrode prepared at 1.0 M aniline concentration, suggesting its highest specific capacitance. Figure b further presents the CV curves at various scan rates for the electrode fabricated at 1.0 M aniline concentration.…”

“…Flexible electrodes with a large energy density ( E ) and high power density ( P ) are key factors for achieving portable and wearable supercapacitors in practical application. The E (μW h cm –2 ) and P (mW cm –2 ) can be, respectively, calculated by the equations: ,,, E = ( C 1 × U 2 )/(2 × 3.6) and P = E / t , where C 1 is the areal capacitance (mF cm –2 ), U is the potential window ( V ), and t is the discharge time ( h ). Figure h depicts the Ragone plot of our assembled device and other recently reported supercapacitors.…”

Rational Design of Coplanar Polypyrrole‐Based Graphene Hydrogels with Excellent Energy‐Storage Performance

“…[24] Previous studies have proposed that these problems can be effectively alleviated by a combination of graphene hydrogels and conductive polymers. [25] The self-assembly strategy has been used to fabricate polyaniline and reduced graphene oxide composite gels with the favorable sandwich structure as a supercapacitor electrode, showing a high specific capacitance about 824 F g À1 at 1 A g À1 with 1 M H 2 SO 4 The ORCID identification number(s) for the author(s) of this article can be found under https://doi.org/10.1002/sstr.202100073. DOI: 10.1002/sstr.202100073 Polypyrrole-based graphene hydrogels (PGRs) are promising candidates for supercapacitor electrodes adapted to portable and wearable energy-storage devices.…”