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As one of the stellar 2D materials, MoS2 remains in the spotlight for its multiple physical and chemical traits that contribute to its high theoretical capacity. But its potential as anode for lithium-ion batteries is hampered by its poor electrical conductivity and its low mechanical stability after cycling. In our research work, we manage to correct these flaws by fabricating MoS2 nanosheets with a physically-lengthened interlayer space through simple plasma evaporation and a gas–solid reaction at a low temperature. The as-synthesized MoS2 nanosheets are uniform, with a BET surface area of 80.42 m2 g−1 and an expanded interlayer distance of 0.702 nm. This material exhibits a high capacity of 860 mAh g−1 at 100 mA g−1, a great rate capability, and stability. Its outstanding electrochemical performance is encouraged by the improved ion conductivity of the enlarged interlayers due to two factors: 1) affording plenty of active Li+ storage sites for fast intercalation/de-intercalation, avoiding sluggish transport, and 2) low energy barrier for reversible lithium insertion at high current densities. The structural configuration is well maintained even after the structure modification during long cycling, where the pulverized Mo nanoparticles are uniformly distributed.

Highly porous carbon film (PCF) coated on nickel foam was prepared successfully by microwave plasma-assisted chemical vapor deposition (MPCVD) with C2H2 as carbon source and Ar as discharge gas. The PCF is uniform and dense with 3D-crosslinked nanoscale network structure possessing high degree of graphitization. When used as the electrode material in an electrochemical supercapacitor, the PCF samples verify their advantageous electrical conductivity, ion contact and electrochemical stability. The test results show that the sample prepared under 1000 W microwave power has good electrochemical performance. It displays the specific capacitance of 62.75 F/g at the current density of 2.0 A/g and retains 95% of its capacitance after 10,000 cycles at the current density of 2.0 A/g. Besides, its near-rectangular shape of the cyclic voltammograms (CV) curves exhibits typical character of an electric double-layer capacitor, which owns an enhanced ionic diffusion that can fit the requirements for energy storage applications.

Bioremediation of polycyclic aromatic hydrocarbons (PAHs) in soil matrix is often arbitrated by the presence of soil organic matter (SOM). The present study focuses on determining the effect of the soil organic content on the mycoremediation of two model PAHs, phenanthrene (Phe) and benzo(a) pyrene (BaP) through microcosm studies. On comparing various microcosm strategies, a maximum degradation of Phe (99%) and BaP (48.5%) in soil bioaugmented with Pleurotus dryinus IBB 903, followed by, biostimulation with the degradation of Phe (89.9%) and BaP (24.8%) were noted. On relating the degradation pattern with lignolytic enzyme cocktail production, a laccase activity of 108 U/Kg at day 21, aryl alcohol oxidase (411 U/Kg) and manganese peroxidase (52.2 U/Kg) at day 14 along with lignin peroxidase (481 U/Kg) at day 21 were noted in fungal augmented soils, which were comparatively higher than levels observed in the bio-stimulation. Investigating the impact of different concentration of SOM (3–12%), a maximum remediation of Phe by 100% at 9% SOM in days 28 and 58.19% for BaP at 12% SOM, respectively was exhibited. Further, the biosorption effect of PAHs in abiotic condition showed a positive correlation with the increase in SOM, with a maximum adsorption of 3.78% Phe, and 6.93% BaP. The results support that the nominal adsorption ability of SOM, and helps in enhancing the microbial growth, thereby improving their degradation potentials, when less than 6% of SOM was utilized. Overall, this work establishes the critical role of organic matter in the soil with reference by simultaneous stimulation and degradation capability in complete PAHs remediation.

Despite possessing a high theoretical capacity, MnS has a rather complex lithium kinetic diffusion and poor mechanical stability that hinders its application in energy storage devices like lithium-ion batteries. This study is focused on overcoming the drawbacks of MnS anode material by assembling a carbon-constraint MnS nanocomposite in a core-shell configuration. This structure is obtained by a simple route involving DC plasma evaporation of Mn@C nanoparticles and posterior thermal sulfurization process. As anode material in a Li-ion battery, MnS@C-300 attains high specific capacity of 890 mAh g−1 after 500 cycles at 500 mA g−1. It also shows remarkable high rate capability with capacity values of 705, 684, 643, 578, and 495 mAh g−1 at current densities of 100, 200, 500, 1000, and 2000 mA g−1, respectively. This exceptional electrochemical response is endorsed to the synergetic effect of the smart design of a core-shell architecture. The carbonaceous shell enhances the lithium-ion diffusion towards the active MnS core and preserves structural stability during the long cycling process.

采用直流电弧法, 在CH 4 气氛下以钨棒为阴极蒸发锰镍混合物阳极靶材, 制备了(Mn 7 C 3 , Ni)@C纳米粒子, 并用作超级电容器电极材料。(Mn 7 C 3 , Ni)@C纳米粒子具有明显的核壳结构, 平均粒径50 nm。在碳外壳包覆下, 内核为Mn 7 C 3 和Ni的混合物。镍有催化作用, 促进碳源形成, 影响C壳厚度, 锰容易与碳结合生成具有赝电容特性的Mn 7 C 3 。镍因其催化作用促进碳壳成长, 使纳米粒子具有双电子层电容。Mn-C化合形成的Mn 7 C 3 具有赝电容特性。因此, 不同锰镍比例对电极电化学性能有极大影响: 锰比例越高, 材料比电容越好(485.12 F/g), 但循环寿命随之变差; 镍比例越高, 材料循环稳定性越好(303.57 F/g), 1000次循环后其比电容保持为原来的70%。