Hierarchical-porous-structured materials have been widely used in the field of electromagnetic wave (EMW) absorption, playing a critical role in minimizing EMW interference and pollution. High-quality EMW absorbers, characterized by a lower thickness, lighter weight, wider absorption band, and stronger absorption capacity, have been instrumental in reducing damage and preventing malfunctions in the automotive and aviation industries. The utilization of discarded nut shells through recycling can not only alleviate environmental problems but relieve resource constraints. Herein, a facile method for the preparation of hierarchical porous biomass carbon derived from abandoned Xanthoceras Sorbifolium Bunge Shell (XSS) biomass was developed for high-performance EMW absorption. The porous structures of XSS biochar were studied by using different levels of the K₂CO₃ activator and simple carbonization. The effect of K₂CO₃ on the EMW parameters, including the complex permittivity, complex permeability, polarization relaxation, and impedance matching, was analyzed. The best EMW absorption performance of the XSS biochar was observed at a mass ratio of activator-to-biomass of 2:1. A minimum reflection loss (RL_min) of −38.9 dB was achieved at 9.12 GHz, and a maximum effective absorption bandwidth (EAB_max) of up to 3.28 GHz (14.72~18.0 GHz) could be obtained at a 1.8 mm thickness. These results demonstrated that hierarchical porous XSS carbon was prepared successfully. Simultaneously, the prepared XSS biochar was confirmed as a potential and powerfully attractive EMW-absorbing material. The proposal also provided a simple strategy for the development of a green, low-cost, and sustainable biochar as a lightweight high-performance absorbing material.

In this study, silver-decorated cerium oxide (Ag@CeO₂) nanoparticles were synthesized through a simple mixing and pyrolysis process to enhance their antioxidant and antitumor properties. The synthesis methods for Ag@CeO₂ were optimized, resulting in nanoparticles with varying antioxidant activities. Notably, the embedding of Ag nanoparticles within CeO₂ during pyrolysis significantly improved the antioxidant activity and stability of the nanoparticles, leading to enhanced antitumor effects. The Ag@CeO₂ nanoparticles exhibited strong cytotoxicity against tumor cells (MCF-7) while maintaining low toxicity toward normal cells (HUVECs). These properties, combined with their ability to modulate mitochondrial membrane potential, position Ag@CeO₂ as a promising candidate for electrochemical therapy (ECT). This study highlights the antioxidant potential and the potential of Ag@CeO₂ nanoparticles in tumor treatment and provides new insights into the application of nanomaterials in ECT.

As a core component of vitamin B12, Co²⁺ is closely associated with the health, life performance, and productivity of ruminants. Therefore, the selective and sensitive detection of Co²⁺ is of great significance. In this work, using the Au–S bond as an “anchor”, a ternary nanocomposite (CDs-AuNPs-GSH) with synergistic functions was constructed by combining gold nanoparticles (AuNPs) with glutathione (GSH) through hydrogen bonding and electrostatic interactions with functional groups on the surface of carbon dots (CDs). The resulting nanocomposite was employed as a fluorescence sensor for Co²⁺ detection. Under optimal conditions at pH 6.0, the sensor exhibited a good linear relationship over the Co²⁺ concentration range of 0.5–125.0 mM, with a limit of detection (LOD) of 0.38 mM. The interaction mechanism between Co²⁺ and the composite was systematically investigated using various characterization methods. The results indicated that Co²⁺, owing to its strong coordination ability, enriches on the surface of the composite, subsequently triggering dynamic fluorescence quenching via an electron transfer pathway. The sensor was successfully applied to determine Co²⁺ in mixed livestock and poultry feed samples, with recovery rates ranging from 89.4% to 103.9%, demonstrating its potential for on-site detection in feed analysis.