Lithium–sulfur batteries are deemed as optimal energy devices for the next generation of high‐energy‐density energy storage. However, several problems such as low energy density and short cycle life hinder their application in industry. Here, MoS2–MoN heterostructure nanosheets grown on carbon nanotube arrays as free‐standing cathodes are reported. In this heterostructure, MoN works as a promoter to provide coupled electrons to accelerate the redox reaction of polysulfides while the MoS2, with a two‐dimensional layered structure, provides smooth Li+ diffusion pathways. Through their respective advantages, both MoN and MoS2 could mutually boost the process of “adsorption‐diffusion‐conversion” of polysulfides, which have a synergy enhancement effect to restrain the lithium polysulfides from shuttling. The designed cathodes show excellent long‐term cycling performances of 1000 cycles at 1C with a low decay rate of 0.039% per cycle and a high rate capability up to 6C. A high initial areal capacity of 13.3 mAh cm−2 is also achieved under a low electrolyte volume/sulfur loading (E/S) ratio of 6.3 mL g−1. This strategy of promoting polysulfide conversion by heterostructure MoS2–MoN as presented in this work can provide a more structured design strategy for future advanced Li–S energy storage systems.

The main challenges of a solar steam generation device based on biomass materials are complicated processing techniques and relatively low efficiency. To solve these problems, we reported a simple immersion treatment method by depositing polydopamine (PDA) and silver nanoparticles (AgNPs) on natural wood to prepare a novel solar interface evaporation device. Ag-PDA@wood exhibits a unique bilayer structure. The absorbance of the top light absorption layer is higher than 96% in a wide wavelength range (300−2500 nm). Owing to the synergistic photothermal effect between PDA and AgNPs, Ag-PDA@ wood has ultrafast solar−thermal response (a temperature increase of 42.5 °C within 5 min under 1 sun), and more heat is located at the steam generation interface (the surface temperature is 45.1 °C). The natural wood layer at the bottom with low thermal conductivity provides sufficient water supply and reduces the bulk heat loss. A high evaporation rate of 1.58 kg m −2 h −1 is achieved using Ag-PDA@wood under 1 sun (1 kW m −2 ). Its evaporation efficiency reaches 88.6%. The results upon sewage treatment and seawater desalination indicate that Ag-PDA@wood has an excellent purification ability and self-desalting capacity. More importantly, when compared to traditional solar evaporators, Ag-PDA@wood exhibits high antibacterial activity. The result of this antibacterial experiment shows that this material almost completely kills harmful bacteria. Therefore, Ag-PDA@wood has a high application potential in seawater desalination and sewage purification, providing a significant incentive to solve the problem of insufficient freshwater supply.

The composites of graphene oxide (GO) nanosheets fabricated by a-Fe 2 O 3 nanorods were prepared through a facile hydrolysis route. As-synthesized a-Fe 2 O 3 nanorods incorporated into GO nanosheets in the composites were observed with diameters of 3-5 nm and lengths of 15-30 nm. The formation mechanism of anchoring a-Fe 2 O 3 nanorods onto GO nanosheets was proposed as the intercalation and adsorption of iron ions onto the surface of GO nanosheets, followed by the nucleation and growth of a-Fe 2 O 3 nanorods. Tribological properties of a-Fe 2 O 3 nanorod/GO composites as lubricating oil additive were investigated by employing a ball-plate tribotester. It is shown that anti-wear and reduced frictional abilities were improved by the addition of a-Fe 2 O 3 nanorod/GO composites into the base oil. The oil with a-Fe 2 O 3 nanorod/GO composites showed better tribological properties than those in the oil with GO nanosheets. Good friction and wear properties of a-Fe 2 O 3 nanorod/GO composites can be explained by the combination of rolling effects between the rubbing surface and formed thin physical tribofilms on the substrate.

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