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Benzoquinone (BQ) electrode is regarded as next generation energy storage material for lithium ion batteries (LIBs) because of its advantages of high theoretical specific capacity, abundant source, environmental friendliness. However, the two key challenges, the dissolution of BQ in organic electrolyte and the low discharge plateaus, impede practical application of BQ as cathode. Here, triphenylamine (TPA) with high working voltage and BQ with high theoretical capacity are used to synthesize triphenylamine‐benzoquinone monomer (TPA‐BQ) and its polymer (poly triphenylamine‐benzoquinone (PTPA‐BQ)) as cathodes for LIBs. The charge/discharge results reveal that the discharge plateaus of TPA‐BQ and PTPA‐BQ increase from ~2.5 V to ~3.5 V, and PTPA‐BQ exhibits high discharge capacity and remarkable cyclic stability compared with TPA‐BQ. The electrochemical mechanism shows that the redox peak potential of ~2.3 V/~2.2 V are assigned to the insertion/extraction of lithium ion in C=O groups of BQ, while at high potential of ~3.6 V/~3.5 V corresponds to the de‐dope/dope of the PF6− anion in TPA unit. The results demonstrate TPA was introduced BQ into small molecule to form PTPA‐BQ polymer that can improve discharge plateaus and charge/discharge performance of BQ small molecule, which provide guides for solving the dissolution and discharge platforms of the other organic electrode materials. [ABSTRACT FROM AUTHOR]

In this study, a carbon‐based nanodemulsifier (ZIF‐8@CNS) was prepared in order to lessen the harmful effects of crude oil emulsion on mechanical equipment and the environment and to provide a green and efficient demulsifier. A novel hydrophilic/lipophilic carbon‐based nanodemulsifier ZIF‐8@CNS was prepared by solvothermal method using ZIF‐8 and carbon nanospheres (CNS) as raw materials. Scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT‐IR) showed that ZIF‐8@CNS was successfully compounded. The interfacial activity experiment showed that the carbon nanospheres combined with ZIF‐8 had better hydrophilic and lipophilic balance and were more easily distributed at the oil‐water interface. The demulsification experiment of water‐in‐toluene emulsion with water content of 1 % was carried out. The results showed that when the dosage of ZIF‐8@CNS with 10 % carbon content was 300 mg/L, the residual water content in the emulsion oil phase was only 0.09 % within 15 min at room temperature. In addition, we propose a possible demulsification mechanism of the demulsifier. ZIF‐8@CNS is environmentally friendly and an effective oil‐water phase separation material with broad application prospects. [ABSTRACT FROM AUTHOR]

The electrochemical performance of carbon based supercapacitors not only depends on the specific surface area and conductivity, but also the structure of materials. In order to construct the carbon materials with effective structure, the long fibrous plant‐saussurea involucrata stalk was chosen as the new style carbon source. Highly ordered micropores activated carbon (HOMAC) materials have been successfully obtained via KOH chemical activation method. The synthesized HOMAC exhibits high specific surface area of 2692 m2 g−1 and pore volume of 1.14 cm3 g−1. The assembled HOMAC‐based electrode can deliver a high specific capacitance of 379 F g−1 at 2 mV s−1 in 1 M H2SO4 aqueous electrolyte, and show excellent cyclic stability (the capacitance retention ∼95 %) over 10000 cycles at a current density of 1 A g−1, which authenticates excellent charge storage capacity of electrode material. Moreover, the operation voltage window can be expanded to 0–1.8 V in 1 M Na2SO4 electrolyte for the 2‐electrode system. The symmetric supercapacitor can deliver a high energy density of 33.91 Wh kg−1 at power density of 180.03 W kg−1. These high performances can be ascribed to the high surface area and ordered microporous structures obtained using KOH as activator. We further discussed the relationship between fibrous plants and electrochemical performances of the final activated carbon materials. This present work can provide beneficial guidance for the preparation of high performance activated carbon electrodes from a biomass‐based carbon source. Comparing with two different biomass materials, it can be found that the ionic diffusion coefficient of saussurea involucrata is 5.074×10−13 m2 s−1, which is 2.5 times of cotton stalk (1.547×10−13 m2 s−1). This phenomenon indicates the different ion transmission rate in different pore structures. [ABSTRACT FROM AUTHOR]

Flexible sensors with excellent sensitivity and stable performance are attracting more and more attention in emerging electronics. Herein, silver microflakes (AgMFs) as conductive filler in polyaniline (PANI)/polyurethane (PU) matrix are used to prepare the AgMFs/PANI/PU strain sensor by simple mixing and curing process. The AgMFs/PANI/PU strain sensor has high sensitivity (GF=173.66), ultra‐short response time (10 ms), and reassuring cycle stability (>4000 times). Excellent sensor performance demonstrates its unlimited potential for health monitoring, such as joint motion, breathing and pulse beat. [ABSTRACT FROM AUTHOR]

Mn‐Fe/ZSM‐5 was prepared via co‐precipitation (CP) and precipitation–chemical vapor deposition (P‐CVD) methods. Catalytic performance investigation showed that Mn‐Fe/ZSM‐5 by P‐CVD method had higher catalytic activity and SO2 resistance than the ones by CP method for NH3‐SCR at low temperature. Characterization results proved that the amount of ammonium sulfate deposited on the surface of Mn‐Fe/ZSM‐5(P‐CVD) was less than that of Mn‐Fe/ZSM‐5(CP) catalyst. Further investigations revealed that the deposition and decomposition of ammonium sulfate proceeded in a dynamic balance on Mn‐Fe/ZSM‐5(P‐CVD) catalyst, which was crucial for the excellent catalytic performances in the presence of SO2 and H2O. Mn‐Fe/ZSM‐5 catalysts were synthesized via co‐precipitation (CP) and precipitation‐chemical vapor deposition (P‐CVD) methods. Excellent SO2 resistence and DeNOx activity over Mn‐Fe/ZSM‐5(P‐CVD) catalyst for NH3‐SCR reaction was confirmed and its intrinsic reason was further revealed. A possible dynamic balance existing between the deposition and decomposition of ammonium sulfate on Mn‐Fe/ZSM‐5(P‐CVD) catalyst was proposed. [ABSTRACT FROM AUTHOR]