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Aqueous zinc-ion batteries (AZIBs) are competitive alternatives for large-scale energy-storage devices owing to the abundance of zinc and low cost, high theoretical specific capacity, and high safety of these batteries. High-performance and stable cathode materials in AZIBs are the key to storing Zn 2+ . Manganese-based cathode materials have attracted considerable attention because of their abundance, low toxicity, low cost, and abundant valence states (Mn 2+ , Mn 3+ , Mn 4+ , and Mn 7+ ). However, as a typical cathode material, birnessite-MnO 2 (δ-MnO 2 ) has low conductivity and structural instability. The crystal structure may undergo severe distortion, disorder, and structural damage, leading to severe cyclic instability. In addition, its energy-storage mechanism is still unclear, and most of the reported manganese oxide-based materials do not have excellent electrochemical performance. Herein, we propose a copper-doped Cu 0.05 K 0.11 Mn 0.84 O 2 ·0.54H 2 O (Cu 2 -KMO) cathode, which exhibits a large interlayer spacing, a stable structure, and accelerated reaction kinetics. This cathode was prepared using a simple hydrothermal method. The AZIB assembled using Cu 2 -KMO showed high specific capacity (600 mA h g -1 at 0.1 A g -1 after 75 cycles). The dissolution-deposition energy storage mechanism of Cu-KMO in AZIBs with double electron transfer was revealed using ex situ tests. The good electrochemical performance of the Cu 2 -KMO cathode fabricated by the doping strategy in this study provides ideas for the subsequent preparation of manganese dioxide using other strategies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Herein, a disubstitution strategy of metal ions and organic ligands is employed to synthesize metal-organic framework (MOF) nanosheets with a three-dimensional (3D) porous structure and a highly active metal-sulfur (M-S, M = Co and Ni) region. The obtained MOFs//Zn batteries exhibit excellent electrochemical properties and the electrochemical reaction mechanism was elucidated through a series of ex situ characterizations.

Metal-organic frameworks (MOFs) are believed to be promising precursors for constructing novel and efficient catalysts for glucose sensing. Herein, HKUST-1 precursors are first fabricated using a one-pot hydrothermal approach, and then HKUST-1 is converted into porous Cu 2 S/CuO octahedrons through conformal sulfidation with the help of OH - ions. The as-obtained Cu 2 S/CuO composite can provide rich electrochemical active sites and promoted electric transfer kinetics. Benefiting from these combined merits, the as-fabricated Cu 2 S/CuO composite is confirmed to be a high-performance catalyst, with high sensitivities of 8269.45 and 4140.82 μ A mM -1 cm -2 in the corresponding ranges of 0.05 ∼ 0.6 mM and 0.6 ∼ 1.2 mM, respectively. Moreover, the as-prepared electrode materials possess good anti-interference ability, reproducibility and long-term stability. This work opens up new avenues for the design and preparation of transition metal sulfide composites., (© 2024 IOP Publishing Ltd.)

Aqueous rechargeable Zn-based batteries (ARZBs) have attracted increasing attention as favorable candidates for energy storage systems due to their high security, environmental friendliness, and abundance of electrode materials. At present, the most widely reported materials used in cobalt-zinc (Co-Zn) batteries are cobalt-based oxides and their derivatives, however, they still exhibit low actual capacities and unsatisfactory cycle lives. Metal-organic frameworks (MOFs), as a new class of porous materials with high specific surface area and adjustable pore size, have attracted considerable attention in the field of energy storage. Currently, pristine MOFs have currently few applications in Co-Zn batteries, and their performance is not ideal. Herein, we report a series of two-dimensional (2D) bimetallic CoM-MOF (M = Ni, Mn, Mg and Cu) nanosheets based on trimesic acid (H 3 BTC) ligand as cathodes for alkaline Co-Zn batteries via a simple one-pot hydrothermal synthesis. Among the synthesized MOFs, the CoNi-MOF nanosheets have the best performance, exhibiting a high reversible capacity of 344 mA h g -1 and demonstrating a good cycling life with 90 % capacity retention at 20 A g -1 after 1500 cycles. The energy storage mechanism is studied through a series of ex-situ characterizations. This study is of great importance in advancing the application of 2D pristine MOFs for high-performance Co-Zn batteries., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Metal-organic frameworks (MOFs) are crystalline porous materials with a long-range ordered structure and excellent specific surface area and have found a wide range of applications in diverse fields, such as catalysis, energy storage, sensing, and biomedicine. However, their poor electrical conductivity and chemical stability, low capacity, and weak adhesion to substrates have greatly limited their performance. Doping has emerged as a unique strategy to mitigate the issues. In this review, the concept, classification, and characterization methods of doped MOFs are first introduced, and recent progress in the synthesis and applications of doped MOFs, as well as the rapid advancements and applications of first-principles calculations based on the density functional theory (DFT) in unraveling the mechanistic origin of the enhanced performance are summarized. Finally, a perspective is included to highlight the key challenges in doping MOF materials and an outlook is provided on future research directions., (© 2024 Wiley‐VCH GmbH.)

Herein, we report the first result of large scale and oxygen vacancy VO 2 porous thin sheets assembled by a 3D interconnected nanoflake array framework, which is recorded as VO d . The as-prepared VO d was characterized by various methods and Zn 2+ intercalation/deintercalation and structural decomposition mechanisms were proposed based on ex situ X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS).

Aqueous zinc ion batteries (AZIBs) and aqueous magnesium ion batteries (AMIBs) offer powerful alternatives for large-scale energy storage because of their high safety and low cost. Consequently, the design of high-performance cathode materials is essential. In this paper, we present a simple strategy that combines oxygen defect (O d ) engineering with a 2D-on-2D homogeneous nanopape-like bilayer V 2 O 5 nH 2 O xerogel (BL-HVO d NPS). This strategy employs O d to improve Zn 2+ /Mg 2+ insertion/extraction kinetics and reduce irreversible processes for high-performance AZIBs/AMIBs. And interlayer water molecules serve as an effective spacer to stabilize the expanded interlayer gap in BL-HVO d NPS, thereby providing extended diffusion channels for Zn 2+ /Mg 2+ during insertion/extraction. The interlayer water molecules help shield the electrostatic interaction between Zn 2+ /Mg 2+ and BL-HVO d NPS lattice, which improves diffusion kinetics during repeated. In addition, electrochemical characterization results indicate that the BL-HVO d  NPS can effectively the surface adsorption and internal diffusion of Zn 2+ /Mg 2+ . More importantly, the successfully prepared unique 2D-on-2D homogenous nanopaper structure enhances electrolyte/electrode contact and reduces the migration/diffusion path of electrons/Zn 2+ and Mg 2+ , thus greatly improving rate performance. As a result, the BL-HVO d NPS as AZIBs/AMIBs electrodes offer better reversible capacity of 361.8 and 162.8 mA h g -1 (at 0.2 A g -1 ), while displaying impressively long cycle lifes. This method provides a way to prepare advanced xerogel cathode materials for AZIBs and AMIBs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Manganese-based materials are considered as one of the most promising cathodes in zinc-ion batteries (ZIBs) for large-scale energy storage applications owing to their cost-effectiveness, natural availability, low toxicity, multivalent states, high operation voltage, and satisfactory capacity. However, their intricate energy storage mechanisms coupled with unsatisfactory cycling stability hinder their commercial applications. Previous reviews have primarily focused on optimization strategies for achieving high capacity and fast reaction kinetics, while overlooking capacity fluctuation and lacking a systematic discussion on strategies to enhance the cycling stability of these materials. Thus, in this review, the energy storage mechanisms of manganese-based ZIBs with different structures are systematically elucidated and summarized. Next, the capacity fluctuation in manganese-based ZIBs, including capacity activation, degradation, and dynamic evolution in the whole cycle calendar are comprehensively analyzed. Finally, the constructive optimization strategies based on the reaction chemistry of one-electron and two-electron transfers for achieving durable cycling performance in manganese-based ZIBs are proposed., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Soil is an essential part of the animal habitat and has a large diversity of microbiota, while the animal body was colonized by a complex bacterial community; so far, the relationship between the animal host microbial community and the soil microbial ecosystem remains largely unknown. In this study, 15 white rhinoceros from three different captive grounds were selected and the bacterial community of the gut, skin, and environment of these rhinoceros were analyzed by 16S rRNA sequencing technology. Our results showed that Firmicutes and Bacteroidota were the predominant phyla in the gut microbiome, whereas skin and environment samples share similar microbiome profiles and are dominated by the phyla of Actinobacteriota , Chloroflexi , and Proteobacteria . Although the bacterial composition of the gut differs from that of the skin and environment, the Venn diagrams showed that there were 22 phyla and 186 genera shared by all the gut, skin, and environmental microbes in white rhinoceroses. Further cooccurrence network analysis indicated a bacterial linkage based on a complex interaction was established by the bacterial communities from the three different niches. In addition, beta diversity and bacterial composition analysis showed that both the captive ground and host ages induced shifts in the microbial composition of white rhinoceroses, which suggested that the bacterial linkage between the captive white rhinoceros and its environment is dynamic. Overall, our data contribute to a better understanding of the bacterial community of the captive white rhinoceros, especially for the relationship between the environment and animal bacterial communities. IMPORTANCE The white rhinoceros is one of the world's most endangered mammals. The microbial population plays a key role in animal health and welfare; however, studies regarding the microbial communities of the white rhinoceros are relatively limited. As the white rhinoceros has a common behavior of mud baths and thus is in direct contact with the environment, a relationship between the animal microbial community and the soil microbial ecosystem appears possible, but it remains unclear. Here, we described the characteristics and interaction of bacterial communities of the white rhinoceros in three different niches, including gut, skin, and environment. We also analyzed the effects of captive ground and age on the composition of the bacterial community. Our findings highlighted the relationship among the three niches and may have important implications for the conservation and management of this threatened species., Competing Interests: The authors declare no conflict of interest.

South China tigers ( Panthera tigris amoyensis , SC) are the most threatened tiger subspecies in the world. All the living SCs are captive in zoos or reserves and depend on artificial feeding. The composition of the gut microbiome plays an important role in sustaining the health of the host. A comprehensive understanding of the composition and development of the microbial community of SC is helpful to improve the feeding of captive SC. In this study, we collected 47 fecal samples, 37 of which were from SC of three developmental stages, 5 from adult Amur tigers (Am), and 5 from adult Bengal tigers (Bg), which were all housed in the same zoo. We investigated the diversity, richness, and composition of the bacterial microbiomes and we found that the gut microbiome of SC is strongly affected by host aging. The composition of the gut microbiome of juvenile SC experienced dramatic changes from 5 months old to 1 year old, and it showed much less difference when compared to the samples of 1 year old and the subadult. No significant differences were observed between the samples of subadult and the adult groups. The predominant phylum of 5-month-old SC is Fusobacteriota (33.99%) when the juvenile tigers were older than 5 months, and Firmicutes , but not Fusobacteriota , became the predominant phylum of bacteria in their gut. The gut microbiome of SC, Am, and Bg is possibly affected by their genetic variation; however, the core microbiome of these three subspecies is the same. Our data suggest that the gut microbiome of SC undergoes a developmental progression: a developmental phase (cub), a transitional phase (subadult), and a stable phase (adult). These results expand our understanding of the role of age in the development of the gut microbiome of SC., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Zhang, Liao, Qin, Ma, Liu, Zou, Huang, Zhong and Yang.)

Self-supported Cu 2 S/Cu(OH) 2 composite nanorods for highly sensitive non-enzymatic glucose sensing were in situ grown on Cu foam by simple hydrothermal treatment of aligned Cu(OH) 2 nanorods. The physicochemical and electrochemical properties of the as-fabricated Cu 2 S/Cu(OH) 2 composite nanorods were characterized by scanning electron microscopy, transmission electron microscopy, x-ray diffraction, Raman spectroscope, x-ray photoelectron spectroscope, cyclic voltammetry, electrochemical impedance spectroscopy, amperometric i - t measurements. The mechanism of the composite nanorods produced on conductive substrates was also explored. The electrode exhibits a sensitivity of 9626.88 μ A mM -1 cm -2 towards glucose with good anti-interference ability, indicating it a promising electrode material for the enhanced non-enzymatic glucose detection., (© 2022 IOP Publishing Ltd.)

Rechargeable alkaline nickel-zinc (Ni-Zn) batteries are attracting increased attention owing to their exceptional inherent safety and high specific capacity. Unfortunately, the limited power and cycling performances of these Ni-Zn batteries are still challenging. Herein, bimetal nickel-cobalt sulfide/ reduced graphene oxide (NiCo-S/RGO) composites with tunable compositions are synthesized by rational designing precursor and subsequent sulfidation treatment. NiCo-S is evenly anchored on RGO surface, resulting in increased number of electrochemical active sites, accelerated electrolyte ion diffusion, and enhanced electrical conductivity. Particularly, by tuning the Ni and Co composition ratios in NiCo-S, NiCo-S/RGO with a Ni to Co ratio of 2:1 (NiCo-S-2/RGO) shows a specific capacity of 145.7 mA h g -1 at 1 A g -1 and long-life cycling retention of 84.7% after 1000 cycles, and the above performances are superior than the controlled samples with other Ni to Co ratios. Furthermore, the as-assembled alkaline zinc batteries of NiCo-S-2/RGO//Zn deliver an impressive specific energy of 333.2 W h kg -1 , showing great potential in practical applications. This experiment hopefully provides new idea for construction of high-performance electrodes of aqueous rechargeable batteries., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The oxygen evolution reaction (OER) with sluggish kinetics is a bottleneck for the large-scale application of water electrolysis. Herein, solid-solution hexagonal Ni 0.5 Co 0.5 Se nanoflakes are designed and successfully synthesized via a facile hydrothermal method with a much lower overpotential of 216 mV at 10 mA cm -2 and a Tafel slope of 37.08 mV dec -1 .

Co(OH) 2 nanosheets/Cu(OH) 2 nanorods composite electrodes for non-enzymatic glucose detection were fabricated by electrodepositing Co(OH) 2 nanosheets on Cu(OH) 2 nanorods substrate grown directly on the copper sheet via a simple one-step reaction. The Co(OH) 2 nanosheets/Cu(OH) 2 nanorods composite electrode was characterized by scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction and x-ray photoelectron spectroscopy. The glucose sensing performance of the composite electrode was investigated by cyclic voltammetry and chronoamperometry. The composite electrode shows high sensitivity of 2366 µA mM -1 cm -2 up to 2 mM with a lower detection limit of 0.17 mM (S/N = 3). The composite electrode is highly selective to glucose in the presence of various substances that always co-exist with glucose in real blood samples. The response of the composite towards human blood serum was in good agreement with that of commercially available glucose sensors, suggesting that a promising electrode material for highly sensitive and selective non enzymatic detection of glucose can be envisioned.