Latest ArticlesRechargeable aqueous zinc-ion batteries have attracted extensive interest because of low cost and high safety. However, the relationship between structure change of cathode and the zinc ion storage mechanism is still complex and challenging. Herein, open-structured ferric vanadate (Fe2V4O13) has been developed as cathode material for aqueous zinc-ion batteries. Intriguingly, two zinc ion storage mechanism can be observed simultaneously for the Fe2V4O13 electrode, i.e., classical intercalation/deintercalation storage mechanism in the tunnel structure of Fe2V4O13, and reversible phase transformation from ferric vanadate to zinc vanadate, which is verified by combined studies using various in-situ and ex-situ techniques. As a result, the Fe2V4O13 cathode delivers a high discharge capacity of 380 mAh/g at 0.2 A/g, and stable cyclic performance up to 1000 cycles at 10 A/g in the operating window of 0.2–1.6 V with 2 mol/L Zn(CF3SO3)2 aqueous solution. Moreover, the assembled Fe2V4O13//Zn flexible quasi-solid-state battery also exhibits a relatively high mechanical strength and good cycling stability. The findings reveal a new perspective of zinc ion storage mechanism for Fe2V4O13, which may also be applicable to other vanadate cathodes, providing a new direction for the investigation and design of zinc-ion batteries.
Carbon dots (CDs) with intriguing fluorescent property, good biocompatibility, high stability, easy interaction with substrates, are burgeoning carbon nanoparticles with large potential in various applications. Incorporating CDs into the polymer matrix is becoming a popular strategy to endow the complex with new functions. Herein, the green-synthesized CDs was integrated into the mixture of gelatin (derived from waste fish scale) and chitosan, and a multifunctional bio-nanocomposite (defined as Gelatin/Chitosan/CDs) film was developed, which showed the excellent antibacterial, antioxidant, pH-sensitivity, UV shielding, and blue-emission properties. The effects of different concentrations of CDs on the physical, mechanical, structural, and functional activity of bio-nanocomposite film were tested. Compared with the Gelatin/Chitosan film, the Gelatin/Chitosan/CDs film with an optimum addition of 20% CDs showed the enhanced antibacterial, antioxidant as well as UV shielding activities. More importantly, it was used as an effective packaging material for fish meat preservation, reducing the loss of nutritional quality consumption, extending the shelf life of food. Besides, the bio-nanocomposite films also possessed the anti-counterfeiting and pH-responsive properties due to the strong fluorescent emission of CDs, and had the great potential in developing the intelligent packaging materials. Our work shed new light on the new application of CDs and the synthesis of bio-nanocomposite film in food industry.
By integrating one strain-many compounds (OSMAC) and LC–MS-based molecular networking strategies, distachydrimanes A–F (1–6), six novel phenylspirodrimane dimers and hybrids representing two types of unprecedented terpenoid-polyketide hybrid skeletons, were isolated from the modified fermented rice substrate of a coral-derived fungus Stachybotrys chartarum. All the structures incorporating their absolute configurations were elucidated based on comprehensive spectroscopic analyses, mainly including HRESIMS and NMR data, single-crystal X-ray diffraction (Cu Kα), and comparison of the experimental electronic circular dichroism (ECD) data. Architecturally, compounds 1–6 represent an unprecedented class of dimeric phenylspirodrimanes with an unexpected C-18–C-23′ linkage, of which compounds 1–3 also feature an unexpected 5-methyl-1, 3-benzenediol moiety via a carbon-carbon linkage. The bioactivity assay demonstrated that compounds 1, 5 and 6 induced cell proliferation inhibition, G0/G1 cell cycle arrest, senescence and mitochondrial-mediated apoptosis in L1210 cells, highlighting their potentials as a new category of anticancer agents.
Lithium–sulfur (Li–S) batteries exhibit outstanding energy density and material sustainability. Enormous effects have been devoted to the sulfur cathode to address redox kinetics and polysulfide intermediates shuttle. Recent attentions are gradually turning to the protection of the lithium metal anodes, since electrochemical performances of Li–S batteries are closely linked to the working efficiency of the anode side, especially in pouch cells that adopt stringent test protocols. This Perspective article summarizes critical issues encountered in the lithium metal anode, and outlines possible solutions to achieve efficient working lithium anode in Li–S batteries. The lithium metal anode in Li–S batteries shares the common failure mechanisms of volume fluctuation, nonuniform lithium flux, electrolyte corrosion and lithium pulverization occurring in lithium metal batteries with oxide cathodes, and also experiences unique polysulfide corrosion and massive lithium accumulation. These issues can be partially addressed by developing three-dimensional scaffold, exerting quasi-solid reaction, tailoring native solid electrolyte interphase (SEI) and designing artificial SEI. The practical evaluation of Li–S batteries highlights the importance of pouch cell platform, which is distinguished from coin-type cells in terms of lean electrolyte-to-sulfur ratio, thin lithium foil, as well as sizable total capacity and current that are loaded on pouch cells. This Perspective underlines the development of practically efficient working lithium metal anode in Li–S batteries.
Buchwald-Hartwig amination of 5, 15-dibromo and 5, 10-dibromo Ni(Ⅱ)porphyrins with 5-amino Ni(Ⅱ)porphyrin gave linear and bent trimers 4Ni and 5Ni with a central quinodiimine-type Ni(Ⅱ)porphyrinoid. The structures of 4Ni and 5Ni have been confirmed by X-ray diffraction analysis in both cases. The formation of unusual products 4Ni and 5Ni has been ascribed to facile oxidation of 5, 15- and 5, 10-amino Ni(Ⅱ) porphyrin unit. Reduction of 4Ni and 5Ni under proper conditions gave NH-bridged Ni(Ⅱ)porphyrin trimers 4Ni-2H and 5Ni-2H in high yields. Trimers 4Ni and 5Ni exhibit the lowest energy band as compared with 4Ni-2H and 5Ni-2H. Especially the bent trimer 5Ni exhibits a broad absorption tail beyond 1400 nm.
The production of graphene oxide with less acid is beneficial to reduce the costs and lower the impact on the environment, but it is still a great challenge. In this work, a relatively simple, safe method for synthesizing graphene oxide with much less acid (decrease ~40%) is proposed. With assistance of the heat absorbed from environment and reaction system, the temperature of reaction system of low acid can be well controlled. More interestingly, the graphite can be completely oxidized into graphite oxide by using much less acid, with lowering the production of high-concentration aqueous waste acid (> 1 mol/L, decrease ~40%). A series of characterizations show that the prepared graphene oxide has similar yield and functional groups compared with that of using the conventional method. This work provides a safe and environmentally friendly choice for the large-scale production of graphene oxide and its derivative materials.
Electrocatalytic nitrogen reduction reaction (NRR) is an environmentally friendly method for sustainable ammonia synthesis under ambient conditions. Searching for efficient NRR electrocatalysts with high activity and selectivity is currently urgent but remains great challenge. Herein, we systematically investigate the NRR catalytic activities of single and double transition metal atoms (TM = Fe, Co, Ni and Mo) anchored on g-C6N6 monolayers by performing first-principles calculation. Based on the stability, activity, and selectivity analysis, Mo2@g-C6N6 monolayer is screened out as the most promising candidate for NRR. Further exploration of the reaction mechanism demonstrates that the Mo dimer anchored on g-C6N6 can sufficiently activate and efficiently reduce the inert nitrogen molecule to ammonia through a preferred distal pathway with a particularly low limiting potential of -0.06 V. In addition, we find that Mo2@g-C6N6 has excellent NRR selectivity over the competing hydrogen evolution reaction, with the Faradaic efficiency being 100%. Our work not only predicts a kind of ideal NRR electrocatalyst but also encouraging more experimental and theoretical efforts to develop novel double-atom catalysts (DACs) for NRR.
A trefoil-like two-dimensional (2D) C3v symmetric organic [12]-imidazolium cation H12–2(PF6)12 featuring three [4]-imidazolium macrocycles was synthesized in three steps. The reaction of a dodecakis H12–1(PF6)12 imidazolium salt with Ag2O resulted in the formation of a hexanuclear AgⅠ dodecacarbene assembly [Ag6(1)](PF6)6. Upon UV irradiation, the photodimerization of the cinnamic ester pendants of [Ag6(1)](PF6)6 led to the generation of a trefoil-like complex [Ag6(2)](PF6)6 containing three closed metallacycles. Removal of metal ions allowed for the synthesis of the target molecule. All complexes were fully characterized by NMR spectroscopy (1H, 13C{1H} and 2D NMR) and high-resolution electrospray ionization mass spectrometry (HR-ESI-MS).
The random movement and easy recombination of photoinduced charges lead to a low conversion efficiency for photocatalytic hydrogen evolution. The cocatalyst design is a promising route to address such problem through introducing an appropriate cocatalyst on the semiconductor photocatalysts to construct the high-efficiency heterojunctions. Herein, novel CoS/Nb2O5 heterojunctions were constructed via in-situ loading CoS cocatalyst on the surface of Nb2O5 nanosheets. Through the femtosecond-resolved transient absorption spectroscopy, the average lifetime of charge carriers for 10 wt% CoS/Nb2O5 (159.6 ps) is drastically shortened by contrast with that of Nb2O5 (5531.9 ps), strongly suggesting the rapid charge transfer from Nb2O5 to CoS. The significantly improved charge-transfer capacity contributes to a high photocatalytic hydrogen evolution rate of 355 μmol/h, up to 17.5 times compared with pristine Nb2O5. This work would provide a new design platform in the construction of photocatalytic heterojunctions with high charge-transfer efficiency.
Aerogels have become a hot topic of research due to their extremely low density and special interconnected structure as well as their enzyme-like activity. The development of new multifunctional nano-enzyme aerogels with high activity and good stability is still a considerable challenge. In this paper, AuRu aerogels with peroxidase and oxidase activities were synthesized using a simple one-step method and successfully used to construct colorimetric sensors for the detection of Fe2+ and glucose based on their enzyme-like activities. Furthermore, we are fortunate to find that AuRu aerogels have good photothermal properties. This suggests that AuRu aerogels can be used not only for in vitro testing but also for promising applications such as disease treatment.
No. 86 Xueyuan South Road, Haidian District, Beijing
010-62199257
qkjq@cast.org.cn
Copyright © 2025 China Association for Science and Technology. All rights reserved. For all open access content, the relevant licensing terms apply.
Sponsored by the Office of the Leading Group for Cybersecurity and Informatization of CAST, and supported by Science and Technology Review Publishing House
