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Recently, the design and development of efficient microwave absorbents by facile engineering approaches have attracted much attention. Particularly, some unique structures caused by cross‐scale design are promising in enhancing the absorbing capability toward microwave irradiation. Herein, the cross‐scale design strategy is implemented to enhance the electromagnetic wave absorption performance of polymetallic sulfides (PMS). In PMS, the dipole polarization unit is optimized, and the distribution of electronic states is improved by doping Ti atoms; Meanwhile, the MS/M3S4 homogeneous hetero‐phases interfaces is constructed in PMS using a phase separation strategy; and the conductivity of PMS is modulated by the addition of acetylene black (ACET). The cross‐scale synergy of microwave absorption leads to a significant enhancement of the microwave absorption (MA) performance of PMS/ACET composites. The optimal reflection loss value of Ti‐LES with 10% ACET addition reaches −55.49 dB and the effective absorption bandwidth reaches 6.73 GHz. The 17.5% ACET‐conditioned Ti‐HES achieves a reflection loss of −37.2 dB at a low frequency of 4.8 GHz. This study not only provides a novel strategy for the development of new broadband MA materials but also validates a new idea for the multi‐scale synergistic optimization of MA materials. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nanomaterials are some of the most promising bifunctional electrocatalysts that can simultaneously catalyze the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). They have attracted extensive attention owing to their decent electrocatalytic performance and cost advantages. In this review, we first provide an overview of 2D bifunctional electrocatalyst categories including layered double hydroxides, graphitic carbon nitride, metal–organic frameworks, transition metal dichalcogenides, and transition metal carbon/nitrogen compounds, and discuss their structures and synthesis methods, presenting detailed discussion on how the special 2D systems are synthesized and characterized experimentally, which complement a comprehensive understanding of the characteristics of 2D bifunctional electrocatalysts. Moreover, we focus on the recent development of 2D nano-catalysts with both HER and OER activity in the field of overall water splitting and summarize some typical strategies for enhancing the bifunctional activities, including doping, nanocomposite construction, interface formation, defect engineering and morphology modulation. The structure–activity relationships are also discussed with the aim of providing guidance in designing novel 2D bifunctional electrocatalysts. Finally, we explore some of the challenges and perspectives that remain in this rapidly growing field. We believe that the systematic and comprehensive contents of this review will stimulate wider research and attention. [ABSTRACT FROM AUTHOR]

A porous ball-flower-like Co3O4/Fe2O3 heterostructural photocatalyst was synthesized via a facile metal–organic-framework-templated method, and showed an excellent degradation performance in the model molecule rhodamine B under visible light irradiation. This enhanced photocatalytic activity can be attributed to abundant photo-generated holes and hydroxyl radicals, and the combined effects involving a porous structure, strong visible-light absorption, and improved interfacial charge separation. It is notable that the ecotoxicity of the treated reaction solution was also evaluated, confirming that an as-synthesized Co3O4/Fe2O3 catalyst could afford the sunlight-driven long-term recyclable degradation of dye-contaminated wastewater into non-toxic and colorless wastewater. [ABSTRACT FROM AUTHOR]

VB‐Group transition metal disulfides (TMDs) are considered excellent materials for electromagnetic wave (EMW) absorption because of their good conductivity and abundant active sites located at their edges and substrates, as compared with VIB‐Group TMDs. Herein, for the first time, EMW absorbers based on VB‐Group NbS2 nanosheets by using a facile one‐step solvothermal method are successfully prepared. The minimum reflection loss (RLmin) can reach up to 43.85 dB with an effective absorption bandwidth of 6.48 GHz (11.52–18.00 GHz). The remarkable EMW absorption performance can also be reflected in the tunable frequency bands (C‐, X‐, and Ku‐bands), which is achieved by adjusting the contents of materials. Furthermore, the influence of the content of 2H‐phase and 1T‐phase in NbS2 on the EMW absorption performance is systematically investigated. The hierarchical hollow‐sphere structure of NbS2 promotes dielectric loss and the multiple reflection and absorption of EMW, and enhances the impedance matching and synergistic attenuation ability. This work demonstrates that the bottleneck of effective absorbing frequency band of single‐component dielectric EMW absorbing materials could be broken through, and paves a novel path towards developing broadband absorbing materials in EMW absorption. [ABSTRACT FROM AUTHOR]