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Transition-metal sulfide is considered to be an admirable transformational electrode material due to low cost, large specific capacity, and good reversibility in lithium-ion batteries (LIBs) and sodium-ion batteries (SIBs). Herein, the reduced graphene oxide-wrapped open bimetallic sulfide (NiS2–Co3S4@rGO) nanocage, derived from nickel–cobalt Prussian blue, was obtained by two-step calcination. There are luxuriant pore structures in the nanocage composite with a specific surface area of 85.28 m2g–1, which provides plentiful paths for rapid transmission of Li+/Na+and alleviates the volume stress caused by insertion and extraction of alkali metal ions. The excellent interface combination of bimetallic sulfide wrapped in reduced graphene oxide improves the conductivity and overall performance of the battery. Thanks to the special interface engineering, the open NiS2–Co3S4@rGO nanocage composite displays rapid lithium storage properties with an average diffusion coefficient of 8.5 × 10–13cm2s–1. Moreover, after 300 cycles, the reversible capacity of the composite is 1113.2 mAh g–1at 1 A g–1. In SIBs, the capacity of the open NiS2–Co3S4@rGO composite is 487.9 mAh g–1when the current density is 5 A g–1. These preeminent performances demonstrate the enormous development prospects of bimetallic sulfide nanocage as anode material in LIBs and SIBs.

Exploiting high-efficiency and low-cost bifunctional electrocatalysts for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) has been actively encouraged because of their potential applications in the field of clean energy. In this paper, we reported a novel electrocatalyst based on an exfoliated two-dimensional (2D) MXene (Ti3C2Tx) loaded with bimetallic oxide alloy nanoparticles (NPs) of Pt and Pd (represented by PtOaPdObNPs@Ti3C2Tx), which was synthesized via solution plasma (SP) modification. The prepared materials were then utilized as highly efficient bifunctional electrocatalysts toward the HER and OER in alkaline solution. At a high plasma input power (200 W), bimetallic oxide alloy nanoparticles of Pt and Pd or nanoclusters with different metallic valence states were deposited onto the Ti3C2Txnanosheets. Because of the synergism of the noble-metal NPs and the Ti3C2Txnanosheets, the electrocatalytic results revealed that the as-prepared PtOaPdObNPs@Ti3C2Txnanosheets under the plasma input power of 200 W for 3 min only required a low overpotential to attain 10 mA cm–2for the HER (−26.5 mV) in 0.5 M H2SO4solution and OER (1.54 V) in 0.1 M KOH solution. Moreover, water electrolysis using this catalyst achieved a water splitting current density of 10 mA cm–2at a low cell voltage of 1.53 V in 1.0 M KOH solution. These results suggested that the hybridization of the extremely low usage of PtOa/PdObNPs (1.07 μg cm–2) and Ti3C2Txnanosheets by SP will expand the applications of other clean energy reactions to achieve sustainable energy.

Hierarchical and hollow porous Fe2O3nanoboxes (with an average edge length of ∼500 nm) were derived from metal–organic frameworks (MOFs) and the gas sensing characteristics were investigated. Sensors based on Fe2O3nanoboxes exhibited a response (resistance ratio) of 1.23 to 0.25 ppm (ppm) hydrogen sulfide (H2S) at 200 °C, the response/recovery speed is fast and the selectivity to H2S is excellent. Remarkably, the sensor showed fully reversible response to 5 ppm of H2S at 50 °C, demonstrating its promise for operating at near room temperature, which is favorable for medical diagnosis and indoor/outdoor environment monitoring. The excellent performance of the Fe2O3nanoboxes can be ascribed to the unique morphology with high specific surface area (SSA) and porous nanostructure.