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Metal oxide incorporated with a conductive polymer have shown great potential as high-performance energy storage devices. In this report, polyaniline wrapped silver decorated manganese dioxide (PANI/Ag@MnO 2) nanorods were successfully synthesized and used as positive electrode material. Cyclic voltammetry, galvanostatic charge discharge and electrochemical impedance spectroscopy were employed to investigate the electrochemical activities. The overall result demonstrates that as prepared PANI/Ag@MnO 2 nanorod performed better supercapacitor activities compared to Ag@MnO 2 and pure MnO 2. The PANI/Ag@MnO 2 nanocomposite exhibited a high specific capacitance of 1028.66 F g−1 at a current density of 1 A g−1 (nearly close to the theoretical capacitance of MnO 2). A detail investigation of the synergic effect of PANI, Ag and MnO 2 on electrochemical properties is presented sequentially. The assembled (PANI/Ag@MnO 2 //AC) asymmetric supercapacitor device showed a high energy density of 49.77 W h kg−1 at power density of 1599.75 W kg−1. The facile and cost-effective production of PANI/Ag@MnO 2 demonstrates a high specific capacitance and energy density with long life cycle introduces this material as a prospective candidate for energy management. Image 1 • PANI/Ag@MnO 2 nanorods was prepared and employed for supercapacitor application. • PANI/Ag@MnO 2 exhibits superior electrochemical performances. • A specific capacitance of 1028.66 Fg−1 was achieved at of 1 A g−1. • High energy (49.77 W h kg−1) and power (1599.75 W kg−1) densities are obtained. [ABSTRACT FROM AUTHOR]

[Display omitted] • A ternary ZnMgAl-LDH@Fe 2 O 3 /3DHPCNF were successfully prepared. • The electrode showed excellent electrochemical activity as both anode and cathode. • The structural and electrochemical effect of Zn has been studied in detail. • The optimized ZnMgAl-LDH@Fe 2 O 3 /3DHPCNF has yielded capacity of 3437 mF cm−2. • The supercapacitor device delivered high energy density of 11.622 mW cm−3 at 9.999 mW cm−3. Nano confinement of Layered double hydroxide (LDHs) nanosheets and metal oxide is a compelling way to develop new functional materials with unique physiochemical features for various energy storage devices with enhanced performance. Herein, ternary zinc-magnesium-aluminum layered double hydroxide (ZMA-LDH) nanosheets and hematite (α-Fe 2 O 3) nanorods are confined in a hetero-interfacial orientation on electrospun three-dimensional hollow and porous carbon nanofibers (3DHPCNF) by a subsequent hydrothermal process, resulting in the formation of a multi-dimensional nanoarchitecture. Such a structure can incorporate a conductive matrix and eliminate the need of current collectors, thereby minimizing the dead mass in electrochemical energy storage materials. The amount of Zn significantly determines the structural, morphological, and electrochemical properties of ZMA-LDH nanostructures. ZMA-LDH@Fe 2 O 3 /3DHPCNF was used as a free-standing electrode material for supercapacitors and endowed high capacitive behavior at both positive and negative working potentials. With the well-arranged 1D-3D hollow and porous interconnection, increased terrestrial surface area, and superior electrical conductivity, the hierarchical composite electrode offers a high areal capacitance of 3437F cm−2 at 1 mA cm−2 and ultrahigh cyclic stability. This fascinating electrochemical performance is attributed to the synergistic effect of 1D/2D/3D hollow and porous nanostructures, bimetallic compositions, top-to-bottom utilization of electrode materials, and unique combinations of surface interfacial diffusion and faradaic reduction governed by carbon and LDH/Fe 2 O 3 , respectively. Furthermore, a flexible all solid-state ZMA-LDH@Fe 2 O 3 /3DHPCNF symmetric supercapacitor exhibited a high areal energy density at a high power density along with excellent cyclability. This result suggests new prospects to design highly efficient multi material based electrodes for energy storage devices. [ABSTRACT FROM AUTHOR]

We report a polyaniline-wrapped, manganese-doped titanium oxide (PANi/Mn-TiO2) nanoparticle composite for supercapacitor electrode and photocatalytic degradation. The PANi/Mn-TiO2 nanoparticles were synthesized using a solvothermal process, followed by oxidative polymerization of aniline. The structural properties of studied materials were confirmed by XRD, FTIR, HRTEM, FESEM, and UV visible spectroscopy. The as-prepared PANi/Mn-TiO2 nanoparticles revealed admirable electrochemical performance with a specific capacitance of 635.87 F g−1 at a current density of 1 A g−1 with a notable life cycle retention of 91% after 5000 charge/discharge cycles. Furthermore, the asymmetric cell with PANi/Mn-TiO2 as a positive electrode exhibited energy density of 18.66 W h kg−1 with excellent stability. Moreover, the PANi/Mn-TiO2 had promising photocatalytic activity for methylene blue degradation. The improved performance of PANi/Mn-TiO2 nanoparticles is attributed to the well-built synergetic effect of components that lead to significant reduction of band gap energy and charge transfer resistance, as revealed by UV visible spectroscopy and electrochemical impedance spectroscopy. [ABSTRACT FROM AUTHOR]