Cross-linking network structures are critical to construct flexible and lightweight electromagnetic (EM) wave absorbers, for which effective regulation of the EM parameters is essential. Herein, a versatile strategy has been developed by interconnecting carbon fibers with NiFe-layered double hydroxide (NiFe LDH)/MXene derivatives. The large-sized flaky morphology and conductive nature of the interconnectors induce the percolation effect in the fabric networks with ultralow addition. As such, efficient adjustment of the EM parameters can be achieved by tuning the content of the interconnectors around the percolation threshold, giving rise to an optimal reflection loss (RL) of −58.0 dB and a wide effective absorption band (EAB) of 7.0 GHz at a thickness of 2.5 mm under the incorporation of 7.0 wt % NiFe LDH/MXene. This work provides insights on constructing percolation networks and effective manipulation of electronic and magnetic properties, which can be extended to various areas such as sensing, catalysis, and energy storage.

Electrocatalytic nitrogen reduction reaction (NRR) is a green and sustainable strategy for artificial nitrogen fixation but remains a significant challenge because of the lack of high-performance electrocatalysts. In this study, flower-like hollow MoSe2 nanospheres as efficient earth-abundant NRR electrocatalysts with a high faradaic efficiency of 14.2% and an ammonia yield of 11.2 μg h–1 mgcat. –1 at ambient conditions were prepared. Such excellent NRR activity can be attributed to the higher specific surface area, more active sites, and longer N2 retention time within the shells because of the design of the hollow structure. Density functional theory calculations were performed to further understand the catalytic mechanism involved. This work demonstrates the feasibility of transition-metal selenides as NRR electrocatalysts and suggests an electrocatalyst materials structure design for efficient electrochemical nitrogen fixation.

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