In this work, a freestanding NiS2/FeS holey film (HF) is prepared after electrochemical anodic and chemical vapor deposition treatments. With the combination of good electrical conductivity and holey structure, the NiS2/FeS HF presents superior electrochemical performance, due to the following reasons: (i) Porous structure of HF provides a large surface area and more active sites/channels/pathways to enhance the ion/mass diffusion. Moreover, the porous structure can reduce the damage from the volumetric expansion. (ii) The as‐prepared electrode combines the current collector (residual NiFe alloy) and active materials (sulfides) together, thus reducing the resistance of the electrode. Additionally, the good conductivity of HF can improve electron transport. (iii) Sulfides are more stable as active materials than sulfur, showing only a small capacity decay while retaining high cyclability performance. This work provides a promising way to develop high energy and stable electrode for Li‐S battery.

A W(Se x S 1−x ) 2 nanoporous architecture (NPA) was developed by facile anodic and chemical vapor deposition treatments. The ternary W(Se x S 1−x ) 2 NPA offers significant advantages toward high-efficiency hydrogen generation: (i) Nanoporous morphology provides more electrochemically active sites to split water. (ii) Lattice mismatch and disordering in the mix-phased W(Se x S 1−x ) 2 film introduce more defects to enhance the catalytic activity. (iii) Conducting 1T phase formed in the strained W(Se x S 1−x ) 2 facilitates the electron transfer during catalytic reactions. Therefore, an onset overpotential of 45 mV and a Tafel slope of 59 mV dec −1 were achieved using the as-prepared W(Se x S 1−x ) 2 NPA.

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Lithium-ion batteries (LIBs) are the most popular and well-commercialized power source for portable electronics. They are gradually making their way to applications in electric vehicles (EVs) and smart grids system with the compelling advantages of high energy density and long cycle life. [1-3] However, the power and energy densities of LIBs are currently considered insufficient to meet the demanding requirements for EVs and other energy storage applications. [4-6] In most commercially available LIBs, graphite-based materials are the mainstream anodes. Nevertheless, the graphite-based anodes are facing a serious bottleneck, because a very limited energy output is delivered for LIBs due to their low theoretical capacity (372 mAh g −1). [7,8] As a consequence, it is vital to develop new types of anode materials with superior capacity performance to replace graphite anodes to build nextgeneration high-performance LIBs. Among the recently examined alternative anodes, the alloying-type anode materials (such as Si, Sn, Al), which operate