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Carbon-based biowaste incorporated with inorganic oxides as a composite is an enticing option to mitigate heavy metal pollution in water resources due to its more economical and efficient performance. With this in mind, we constructed manganese-doped iron oxide microflowers resembling the dandelion-like structure on the surface of cold plasma-treated carbonized rice husk (MnFe 2 O 3 /PCRH). The prepared composite exhibited 45% and 19% higher removal rates for Cu2+ and Cd2+, respectively than the pristine CRH. The MnFe 2 O 3 /PCRH composite was characterized using XRD, FTIR, FESEM, EDX, HR-TEM, XPS, BET, TGA, and zeta potential, while the adsorption capacities were investigated as a function of pH, time, and initial concentration in batch trials. As for the kinetics, the pseudo-second-order was the rate-limiting over the pseudo-first-order and Elovich model, demonstrating that the chemisorption process governed the adsorption of Cu2+ and Cd2+. Additionally, the maximum adsorption capacities of the MnFe 2 O 3 /PCRH were found to be 122.8 and 102.5 mg/g for Cu2+ and Cd2+, respectively. Based on thorough examinations by FESEM-EDS, FTIR, and XPS, the possible mechanisms for the adsorption can be ascribed to surface complexation by oxygen-containing groups, a dissolution-precipitation of the ions with –OH groups, electrostatic attraction between metal ions and the adsorbent's partially charged surface, coordination of Cu2+ and Cd2+ with π electrons by aromatic/graphitic carbon in the MnFe 2 O 3 /PCRH, and pore filling and diffusion. Lastly, the adsorption efficiencies were maintained at about 70% of its initial adsorption even after five adsorption-desorption cycles, displaying its remarkable stability and reusability. [Display omitted] • Mn-doped Fe 2 O 3 microflowers were decorated on plasma-treated biochar (MnFe 2 O 3 /PCRH). • The MnFe 2 O 3 /PCRH was thoroughly analyzed before and after Cu2+ and Cd2+ adsorption. • Kinetics, isotherms, and thermodynamic studies showed its excellent adsorption capability. • Mechanisms underlying ions adsorption by MnFe 2 O 3 /PCRH were further clarified. • The reusability of the MnFe2O3/PCRH proved its economic sustainability. [ABSTRACT FROM AUTHOR]

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] • Ag@TiO 2 NFs were synthesized by solvothermal route followed by photoreduction method. • Antibacterial study was performed with Gram positive (Staphylococcus aureus) and Gram negative (Escherichia coli) bacteria. • The Ag (2 wt%) @TiO 2 NFs has more antibacterial effect against both type of bacteria. Silver nanoparticles (Ag NPs) decorated Titanium dioxide nanoflakes (TiO2 NFs) were synthesized via solvothermal followed by photoreduction method. As synthesized TiO 2 NFs and Ag@TiO 2 NFs were characterized by Field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier transform infra-red (FTIR) spectroscopy. The impact of Ag@TiO 2 NFs as antibacterial agents against Gram positive Staphylococcus aureus and gram-negative Escherichia coli was investigated. The obtained results revealed that the Ag@TiO 2 NFs were potential antibacterial agents compared to TiO 2 NFs only. Moreover, among of various samples Ag (2 wt%) @TiO 2 NFs was more effective with compared to other samples. [ABSTRACT FROM AUTHOR]

In this study, quaternized poly (arylene ether sulfone) (QNPAES) was synthesized using conventional nucleophilic aromatic polycondensation. We then developed a blended membrane composed of sulfonated poly (ether ether ketone) (SPEEK) using facile solution casting. A series of mixed hybrid membranes of SPEEK/QNPAES were prepared by varying the wt% of QNPAES mixed with SPEEK. The results showed that an appropriate amount of QNPAES (i.e., 6 wt%) could significantly improve the mechanical strength, proton conductivity and physicochemical properties of a prepared mixed membrane, as well as the proton exchange membrane fuel cell (PEMFC) performance and durability at relative humidity (RH) of 20%. Specifically, a SPEEK/QNPAES at 6 wt% provides a current output, power output and endurance of 0.431 A cm−2, 0.15 W cm−2 and over 900 h, respectively, at an RH of 20% and 60 °C. These results can be attributed to acid-base ionic crosslinking, which offers effective interfacial compatibility between SPEEK and QNPAES. A PEMFC with SPEEK/QNPAES membranes when used at 20% RH achieved significantly advanced performance and ultra-high, long-term durability compared with those of PEMFCs with bare SPEEK, suggesting that SPEEK/QNPAES membranes can be used as polymer electrolyte membranes. Proton transport of SPEEK/QNPAES acid-base blended membranes for PEFC performance and ultra-high, long-term durability over 900 h. [Display omitted] • QNPAES was synthesized using conventional nucleophilic aromatic polycondensation. • The SPEEK/QNPAES (6 wt%) demonstrated significantly improved proton conductivity. • Acid-base crosslinking offers effective compatibility between SPEEK/QNPAES. • The SPEEK/QNPAES provides maximum current output and power density. • The SPEEK/QNPAES exhibits long-term durability under 20% RH for 900 h. [ABSTRACT FROM AUTHOR]

Transition bimetallic compounds are exploited as high-capacity electrode materials for supercapacitors due to their abundant electroactive sites and electrical conductivity. However, it remains grand challenge to construct supercapacitor devices that deliver high energy density. Here, we report an attractive one-stone-two-birds strategy to develop metal organic frameworks (MOFs) derived cathodes and anodes consisting of zinc cobalt telluride integrated nitrogen doped carbon (ZnCoTe–N–C) and zinc cobalt nanoparticles encased nitrogen doped carbon nanotubes (ZnCo-NPs-N-CNTs), respectively. Particularly, ZnCoTe–N–C cathode exhibited high specific capacity of 192.77 mA h g−1, which was further improved by the presence of hierarchical molybdenum disulfides (MoS 2) nanosheets. Increased electrochemical active sites provided by MoS 2 nanosheets energizes both the capacity and stability of the electrode. Consequently, the ZnCoTe–N–C/MoS 2 electrodes showed a higher specific capacity of 342.55 mA h g−1 as well as excellent long-term stability. Besides, the ZnCo-NPs-N-CNTs demonstrated an initial capacity of 207.22 mA h g−1 and retained a high specific capacity even after 50 A g−1. The excellent electrochemical activity of the electrodes is attributed to the incorporation of redox rich bimetallic components and nitrogen rich carbon directly grown on the current collector, which reduces the dead volume and avoids volume expansion during charge discharge process. Finally, a hybrid asymmetric supercapacitor (HASCs) assembled using ZnCoTe–N–C/MoS 2 and ZnCo-NPs-N-CNTs delivered a high specific energy density and power density maintaining 93.6% of its capacitance after 20,000 cycles. This study expands a way to construct a hybrid supercapacitor with well-designed structure and superior performance for clean energy storage technologies utilizing minimum resources. [Display omitted] • ZnCo-MOF is utilized to obtain cathode and anode for hybrid supercapacitor. • Cathode: ZnCoTe–N–C/MoS 2 exhibited high specific capacity of 342.55 mA h g−1. • Anode: ZnCo-NPs-N-CNTs maintains excellent rate capability and stability. • HASCs delivered incredible specific energy density 108.41 W h kg−1. [ABSTRACT FROM AUTHOR]

Environmental remedies, including adsorption-based water purification, are now being asked to meet the requirement for a low-carbon circular economy requiring low energy and low material consumption. In this regard, we tested the possibility of regenerating adsorbents via cold plasma (CP) treatment for less use of adsorbents and no washing solution. In the adsorption of methylene blue (MB) using carbonized rice husk (CRH) and five successive regeneration cycles by CP treatment, the removal efficiencies were maintained at a moderate level (∼70% of the initial performance), unlike five consecutive adsorption without CP treatment (∼9–13% of the initial performance). The regeneration of CRH by CP treatment was also double-checked by the FESEM, EDS, BET, FTIR, XPS, and surface zeta potential measurements. The successfully recovered adsorption capability is related to the remediation of adsorption sites. It is also worth noting that the required power consumption for recycling by CP treatment was about 6.4 times lower than carbonizing new rice husks. This work provides insights into recovering adsorbents using CP without rigorous, costly, and energy-intensive processes. [Display omitted] • Carbonized rice husk (CRH) was used for adsorption-based removal of dye molecules. • The adsorption kinetics was governed by the pseudo-second-order model. • Cold plasma (CP) treatment successfully regenerated the dye-adsorbed CRH. • CP treatment was workable for the five consecutive adsorption tests of the used CRH. • The regeneration mechanism was discussed in detail based on thorough analyses. [ABSTRACT FROM AUTHOR]