Baoliang Zhang

Covalent integration of DACP into polyurea enables balanced mechanical toughness and flame retardancy through molecular-level reinforcement and graphitized char barrier formation.

Metal–organic frameworks (MOF) and conventional bioadsorbents, such as UiO‐66‐NH ₂ and poplar cellulose fibers (PCF), often suffer inefficient charge separation, limited uranium binding affinity, and severe biofouling, restricting their performance in seawater. Here, we report a cellulose‐based aerogel catalyst incorporated with shrimp‐derived carbon dots (SCD) and a MOF heterojunction network (SCD‐MOF@PCF) with engineered interfacial structures and a regulated coordination environment. The interfacial coupling between SCD and UiO‐66‐NH ₂ enhances visible‐light harvesting, promotes charge separation, and enriches photogenerated electrons at Zr sites, strengthening uranium coordination, elongating the U–O bond, and lowering the energy barrier. Density functional theory calculations reveal a maximum adsorption energy of −6.99 eV, consistent with the experimentally observed high adsorption capacity of 899.94 mg g ⁻¹ . In natural seawater, the catalyst achieves a uranium uptake of 7.13 mg g ⁻¹ after 3 weeks. Additionally, light induces the production of reactive oxygen species, thereby mitigating biofouling, enabling sustainable and efficient uranium extraction.

Graphdiyne (GDY), an emerging two-dimensional carbon material, requires the construction of composite structures/components to synergize multiple loss mechanisms for its further advancement in microwave absorption. This study employed a multicomponent complementary strategy to design and fabricate a N-doped GDY composite loaded with Co particles (Co/N-GDY) as a microwave absorbing material. By coupling the advantages of the sp/sp2 hybridized carbon network of GDY, N atom doping, and Co nanoparticles, precise regulation of the dielectric properties and impedance matching characteristics of GDY was achieved. Mechanistic investigations based on first-principles calculations reveal that revealed that N-doping not only enhanced dipole polarization but also effectively mitigated potential adverse electrical effects induced by the Co particles. Concurrently, the Co nanoparticles induced strong interfacial polarization by creating abundant heterogeneous interfaces, thereby compensating for the loss limitations associated with single N-doping. The resulting Co/N-GDY composite exhibited exceptional microwave absorption performance within the 2–18 GHz frequency band. At a minimal matching thickness of merely 1.8 mm, the material achieved a wide effective absorption bandwidth (EAB) of 5.08 GHz and a minimum reflection loss (RLmin) of −56.91 dB. This work offers a novel strategy for designing high-performance microwave absorption materials and is expected to promote the application of GDY in electromagnetic functional materials.

The objective of this study was successfully achieved by engaging undergraduate students in the preparation and application of covalent organic frameworks (COFs) for the colorimetric detection of uranium. The COFs were synthesized via a one-step condensation reaction followed by nucleation, both of which were accessible and manageable for undergraduate training. Characterization of the COFs and the subsequent experimental procedure were conducted with students, and the resulting data were analyzed and plotted using Origin software. The interaction between COFs and uranium ions demonstrated their effectiveness as a sensor, with a UV–visible absorption spectrophotometer used as the primary detection method. This approach achieved an average limit of detection (LOD) of 1.74 μM with a concentration range of 2.1–13.8 μM. This work highlights several key advantages: (i) the use of a straightforward and environmentally friendly condensation method for COFs preparation, (ii) the feasibility of a 72 h nucleation process suitable for undergraduate laboratory practice, and (iii) the adoption of a colorimetry detection method that is sensitive, cost-effective, and easy to operate. Overall, this experiment provided students with valuable experience in material synthesis, data analysis, and application of UV–visible absorption spectroscopy for real-world environmental challenges, thereby strengthening both their experimental and conceptual understanding of chemistry.

Multispectral compatible stealth materials are essential for modern military platforms to counter diverse detection threats. However, the inherent mechanism conflict between microwave absorption and infrared stealth hampers cross-band stealth in single-material systems. Herein, 2D Cu-HHTP/rGO functional fillers are embedded into a solid-solid phase change polyurethane (SHPEG) matrix to fabricate a flexible, self-healing composite film (Cu-HHTP/rGO/SHPEG) with radar-infrared dual-stealth. A synergistic regulation strategy of Schottky heterointerfaces and electrical conductivity is proposed, which induces a built-in electric field and optimizes dielectric loss. Cu-HHTP/rGO attains outstanding microwave absorption with a minimum reflection loss (RLmin) of -60.49 dB and an effective absorption bandwidth (EAB) of 7.51 GHz. Meanwhile, the dynamic cross-linking network modified with disulfide bonds ensures self-healing ability and structural stability of the SHPEG matrix. Based on the excellent thermal management capacity of SHPEG and the low infrared emissivity of Cu-HHTP/rGO, the Cu-HHTP/rGO/SHPEG film possesses remarkable integrated performance: RLmin reaching -52.8 dB, EAB covering 7.29 GHz, infrared emissivity as low as 0.240 and a phase transition enthalpy of 95.1 J/g. The composite film also exhibits exceptional flexibility, self-healing efficiency, shape stability and mechanical strength. This work provides new insights for resolving multiband stealth conflicts and promotes the development of advanced radar-infrared bifunctional materials.

Developing cost-effective and straightforward methods for the efficient adsorption of U(VI) from seawater is essential for promoting both energy security and environmental sustainability. In this study, a series of bio-composites-GO@Cel, including GO@Cel/PAN and GO@Cel-PAO, were successfully fabricated using cellulose (Cel), graphene oxide (GO), and polyacrylonitrile (PAN) via a new blending-evaporation method for efficient uranium adsorption. The results presented that GO@Cel-PAO showed a U(VI) adsorption capacity of 384.63 mg/g, followed by the Langmuir and pseudo-second-order models, suggesting monolayer chemisorption. Moreover, the uranium adsorption onto the GO@Cel-PAO was spontaneous and endothermic in nature, with an adsorption efficiency of 99.25% in seawater. In addition, GO@Cel-PAO showed the regeneration efficiency of 90% after five consecutive adsorption-desorption cycles, demonstrating an efficient and recyclable adsorbent material for practical seawater uranium extraction and environmental remediation.

Electrosynthesis of 1,3-butadiene from acetylene offers a promising alternative to energy-intensive industrial processes. Nonetheless, achieving selective hydrodimerization of acetylene remains challenging due to competing side reactions, particularly for dilute coal-derived acetylene. Herein, we synthesize a series of dicopper paddlewheel Cu₂(LCOO)₄ (L = tert-butyl, isopropyl, ethyl, and methyl), featuring bidentate bridging carboxylate ligands with specific Cu···Cu distances for electrocatalytic hydrodimerization of acetylene to 1,3-butadiene. Through catalyst benchmarking, in situ spectroscopy and computational analysis, we reveal that sequential modulation of carboxylate ligands (methyl → ethyl → isopropyl → tert-butyl) progressively enriches electron density at dicopper sites while strengthening structural robustness across the Cu₂(LCOO)₄ series. The optimized Cu₂(tert-butylCOO)₄ exhibits favorable reaction energetics for acetylene dimerization and subsequent hydrogenation, achieving 91% Faradaic efficiency with a 1,3-butadiene formation rate of 0.93 mmol h^-1 cm^-2 in a flow cell. For simulated production of 1,3-butadiene from coal-derived acetylene (15%) in a membrane electrode assembly system, this catalyst demonstrates 83% Faradaic efficiency at -300 mA. This work highlights an effective coordination modulation strategy for producing 1,3-butadiene via dicopper molecular catalysts.

Graphdiyne (GDY) possesses a unique electronic structure; however, its application in microwave absorption is severely restricted by insufficient electrical conductivity and impedance mismatch. Herein, an interfacial engineering strategy is proposed to overcome these limitations. By constructing graphene/graphdiyne (GR/GDY) heterostructures, the interfacial characteristics and charge distribution were effectively modulated, thereby enhancing the electromagnetic wave loss capability of GDY. The intriguing unidirectional growth of GDY on the GR surface is systematically investigated, elucidating the mechanism of liquid–liquid interface‐induced lateral epitaxial growth. Through precise optimization of the GR‐to‐GDY ratio, a 3D sheet‐like composite with excellent wave absorption performance was successfully fabricated. The optimized absorber achieved a minimum Reflection Loss (RL _min ) of −44.95 dB and a broad effective absorption bandwidth (EAB) of 5.57 GHz at a thin thickness of 2.2 mm. Theoretical calculations and experimental results demonstrate that the superior performance stems from the synergy of interfacial polarization, dipole polarization, and conductive loss, coupled with optimal impedance matching. The construction and structural optimization of the GR/GDY composite absorber provide a strong impetus for expanding the application of GDY in the field of microwave absorption.

Enhancing the conduction and polarization properties of the emerging two-dimensional carbon material graphdiyne (GDY) represents a crucial step in broadening its application in microwave absorption. A novel strategy was proposed to improve the microwave absorption performance of GDY through precise regulation of single-atom structures. Using three-dimensional spherical GDY as a substrate, Two Fe single-atom absorbers were successfully constructed: one anchored by Fe–N-GDY (FeN ₂ C ₂ ) via sp -N/ sp -C cooperative coordination, and the other anchored by Fe-GDY (FeC ₄ ) via sp -C coordination alone. Combined experimental characterization and theoretical calculations revealed that the FeN ₂ C ₂ configuration induces stronger charge transfer and dipole polarization. This effect synergistically optimizes both the dielectric loss and impedance matching of the material. Consequently, the optimal sample Fe–N-GDY achieved an effective absorption bandwidth of 5.98 GHz at a matched thickness of 2.0 mm, with a minimum reflection loss of −51.2 dB. The strategy was further extended to multiple 3 d transition metals (Cr, Mn, Co, Ni, Cu, and Zn). Results indicate that Group VIII elements (Fe, Co, Ni) exhibit superior performance in practical materials due to their electronic structures that favor balancing polarization and conduction losses. Radar cross section simulations confirm the exceptional attenuation capabilities of this series of absorbers in real-world scenarios. This work not only pioneers new applications for GDY in microwave absorption but also establishes a theoretical foundation for rationally designing atomically precise electromagnetic functional materials by revealing the “single-atom structure–property” correlation.