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The metal‐organic framework (MOF) derived Ni–Co–C–N composite alloys (NiCCZ) were "embedded" inside the carbon cloth (CC) strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion application. The NiCCZ was then oxygen functionalized, facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization, generating a flower‐like metal hydroxysulfide structure (NiCCZOS) with strong partial implantation inside CC. Thus obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three‐electrode configuration. Moreover, when paired with the biomass‐derived nitrogen‐rich activated carbon, the asymmetric supercapacitor device shows almost 100% capacity retention even after 45,000 charge–discharge cycles with remarkable energy density (59.4 Wh kg–1/263.8 µWh cm–2) owing to a uniquely designed cathode. Furthermore, the same electrode performed as an excellent bifunctional water‐splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction (OER) and 168.4 mV for hydrogen evolution reaction (HER) at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and OER. Hence, a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications. [ABSTRACT FROM AUTHOR]

We report a greener, effortless, and scalable approach involving the synthesis of a self-grown nanomaterial on a flexible conductive substrate along with the synthesis of activated carbon derived from biomass waste. Contrary to the popular idea of using a variety of additives for the synthesis of nanomaterials, such as surface-activating agents, 3d metal-oxide nanoplates were synthesized on a highly hydrophobic carbon cloth substrate using no foreign elements except the metal precursors. The activated carbon was derived from biomass waste in that it was synthesized using withered cherry flower petals. The two as-synthesized materials were combined to fabricate an asymmetric supercapacitor, the design of which is presented as a greener and sustainable way to obtain an alternative energy storage unit. The three-dimensional nanoplate architecture from the positive electrode combined with the densely populated meso-/microporous structures of the negative electrode delivered an energy density of 106.3 μWh cm–2 for a power density of 657 μW cm–2, which is maintained at 57.5 μWh cm–2 even at a high power density of 5283.4 μW cm–2. Furthermore, a highly stable rate performance was achieved with high capacity retention even after charging–discharging for over 6000 cycles. The fabricated device exhibits highly satisfactory results in practice and hence presents itself as a highly capable candidate for a green energy solution. [ABSTRACT FROM AUTHOR]

An essential key to enhancing the specific capacity and cyclic stability of transition metal oxide materials is the hybridization of carbon compounds by binder-free methods for supercapacitors. Carbonaceous compounds shorten the electron-ion diffusion pathways due to their high active surface area and conductivity. Herein, we focus on improving the specific energy, stability, and conductivity of the electrode by the incorporation of nanosized carbon material. The integration of nano carbons from viable eco-friendly glucose with CoMoO4 enhanced the experimental specific capacity of the electrode. The self-grown CoMoO4 on a nickel foam (CMO-NF) was confirmed as the best approach after extensive optimization process by the feasible hydrothermal (HT) method. The amount of carbon deposited and the structural morphology on the fabricated CoMoO4-glucose-derived carbon (CMO-GC) electrode was varied by adjusting the concentration of glucose by the viable HT technique. Notably, the hybrid CMO-GC-2 achieved a maximum specific capacity of 851.85 C g−1 at 1 A g−1, and it is relatively higher than that of CMO-NF (301.4 C g−1). The asymmetric supercapacitor device (CMO-GC-2//AC) demonstrated excellent energy density (36.86 W h kg−1 for 152.84 W kg−1), power density (3209.35 W kg−1 for 11.19 W h kg−1), and extensive capacity retention of 87% for up to 5000 cycles. The high performance is related to the synergetic effect of EDLC and the redox reaction, with nano-architecture and well-defined morphology of the electrode material. [ABSTRACT FROM AUTHOR]

A two-stage plasma catalyst system for high-throughput NO x removal was investigated. Herein, the plasma stage involved the large-volume plasma discharge of humidified gas and was carried out in a sandwich-type honeycomb monolith reactor consisting of a commercial honeycomb catalyst (50 mm high; 93 mm in diameter) located between two parallel perforated disks that formed the electrodes. The results demonstrated that, in the plasma stage, the reduction of NO x did not occur at room temperature; instead, NO was only oxidized to NO 2 and n -heptane to oxygenated hydrocarbons. The oxidation of NO and n -heptane in the honeycomb plasma discharge state was largely affected by the humidity of the feed gas. Furthermore, the oxidation of NO to NO 2 occurs preferably to that of n -heptane with a tendency of the NO oxidation to decrease with increasing feed gas humidity. The reason is that the generation of O 3 decreases as the amount of water vapor in the feed gas increases. Compared to the catalyst alone, the two-stage plasma catalyst system increased NO x removal by 29% at a temperature of 200 °C and an energy density of 25 J/L.

An essential key to enhancing the specific capacity and cyclic stability of transition metal oxide materials is the hybridization of carbon compounds by binder-free methods for supercapacitors. Carbonaceous compounds shorten the electron-ion diffusion pathways due to their high active surface area and conductivity. Herein, we focus on improving the specific energy, stability, and conductivity of the electrode by the incorporation of nanosized carbon material. The integration of nano carbons from viable eco-friendly glucose with CoMoO4 enhanced the experimental specific capacity of the electrode. The self-grown CoMoO4 on a nickel foam (CMO-NF) was confirmed as the best approach after extensive optimization process by the feasible hydrothermal (HT) method. The amount of carbon deposited and the structural morphology on the fabricated CoMoO4-glucose-derived carbon (CMO-GC) electrode was varied by adjusting the concentration of glucose by the viable HT technique. Notably, the hybrid CMO-GC-2 achieved a maximum specific capacity of 851.85 C g-1 at 1 A g-1, and it is relatively higher than that of CMO-NF (301.4 C g-1). The asymmetric supercapacitor device (CMO-GC-2//AC) demonstrated excellent energy density (36.86 W h kg-1 for 152.84 W kg-1), power density (3209.35 W kg-1 for 11.19 W h kg-1), and extensive capacity retention of 87% for up to 5000 cycles. The high performance is related to the synergetic effect of EDLC and the redox reaction, with nano-architecture and well-defined morphology of the electrode material.