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Transition-metal selenides have attracted extensive concern as one of the alternatives for sodium-ion batteries (SIBs) anodes due to their high theoretical capacities, good cycling stability and environmental benignity. However, the application of metal selenides is restricted by severe volume variation and sluggish kinetics during cyclings, which cause capacity fading induced by the pulverization and aggregation of the electrode materials. Herein, the FeSe 2 @C microspheres assembled with FeSe 2 nanoparticles cotaed by carbon layers are fabricated using a hydrothermal method and the subsequent annealing treatment. When served as anodes for SIBs, the FeSe 2 @C electrodes exhibit excellent electrochemical performances. A high reversible capacity of 461 mA h g−1 is retained after 100 cycles at 50 mA g−1. Even at high rate of 1000 mA g−1, a long-term cycling capacity of 428 mA h g−1 is achieved after 1000 cycles. The kinetic analyses confirm that the superior sodium storage performances of FeSe 2 @C composites are mainly attributed to the pseudocapacitive contribution facilitated by the unique nano-micro hierarchical structure. The FeSe 2 @C microsphere has many pores, which offer enough space for volume expansion during discharge, and shorten the diffusion path of electrons and Na+ ions. The carbon layer can significantly enhance the mechanical stability, improve the electron conductivity, and suppress the volume expansion of the electrode during the cyclings. When served as anode for SIBs, the FeSe 2 @C exhibits a good cycling stability and superior rate performance. Image 1 • The FeSe 2 @C are fabricated through hydrothermal method and annealing treatment. • The FeSe 2 @C microsphere is assembled by FeSe 2 nanoparticles coated by carbon layer. • The FeSe 2 @C electrode exibits excellent battery performance in SIBs. • The excellent performance is mainly ascribed to the pseudocapacitive contribution. [ABSTRACT FROM AUTHOR]

Herein, a hierarchical architecture for high‐performance flexible lithium/sodium‐ion batteries (LIBs/SIBs) is reported, which comprises the interconnected carbon fiber cloth network (CC) decorated with MoS2 microflowers assembled by ultrathin MoS2 nanosheets (MoS2/CC) through an in situ hydrothermal method and a subsequent calcination treatment. When used as a flexible binder‐free anode, the MoS2/CC electrode shows an amazing cyclicality and a high reversible capacity for both lithium and sodium storages. As for LIBs, the MoS2/CC composite delivers a high specific capacity of 1263 mAh g−1 after cycled for 100 cycles at 0.1 A g−1. A rate capacity of 838 mAh g−1 can be obtained at 2 A g−1 after 100 cycles. As for SIBs, a reversible capacity of 515 mAh g−1 can be retained after 100 cycles at 0.1 A g−1. The enhanced electrochemical properties of MoS2/CC can be attributed to the following three synergic effects: 1) the carbon network offers an amazing conductivity environment without any binder or additive; 2) the sheet‐like structure of MoS2 provides the short Li ions diffusion path and can accommodate stress during cyclings; and 3) the 3D architecture ensures the well‐preserved structural integrity. The above results show that the MoS2/CC composite holds great promise as a flexible anode for practical applications in next‐generation LIBs and SIBs. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs)-assisted microbes and enzymes are potential approaches for converting lignocellulosic biomass into fermentable sugars in a biorefinery. In the present study, an ILs-tolerant strain Aspergillus terreus NEAU-7 with ILs-stable cellulase production ability was isolated and identified. A comparative transcriptome analysis revealed that A. terreus NEAU-7 could promote ion transport and acquire metabolic energy to reduce the adverse effect of ILs. The results further confirmed that the strain could increase the accumulation of compatible solutes to offset the osmotic pressure of ILs and reduce the cell membrane permeability to prevent ILs. A secretome analysis of Carbohydrate-Active Enzymes (CAZymes) showed no significant reduction in the Glycoside Hydrolases (GH) families of cellulolytic enzymes, while a significant reduction was observed for Carbohydrate Esterases (CE) families and Glycoside Hydrolase 43 (encoding α- L -arabinofuranosidases and β-xylosidases), indicating that the presence of ILs could decrease the expression of hemicellulolytic enzymes. Herein, a model for lignocellulose degradation of A. terreus NEAU-7 was interpreted. Overall, this study will provide insights into further exploration of the ILs-resistance mechanism of lignocellulolytic fungi and employment of ILs-assisted fungi in the degradation of lignocellulosic biomass into value-added products. [Display omitted] • ILs-tolerant Aspergillus terreus produced 19.27 U/mL of ILs-stable endoglucanase. • The strain accelerated the ion transport to reduce the adverse effect of ILs. • The strain accumulated the compatible solutes to offset the osmotic pressure of ILs. • The strain reduced the permeability of cell membrane to prevent ILs. • No significant reduction of cellulolytic enzymes was found according to secretome. [ABSTRACT FROM AUTHOR]