The infectious diseases caused by various bacteria pose serious threat to human health. To solve this problem, antibacterial agents have been widely used in people’s daily life to deactivate or kill these bacteria. Among the antibacterial agents, ZnO is one of the most promising metal oxide antibacterial agents due to its non-toxic nature and safe properties. To expand its application, many composites of ZnO have been widely studied. Cellulose, as one of the most abundant biopolymers, has many merits like biodegradability, biocompatibility and low cost. Thus, many studies focus on synthesized cellulose/ZnO. The synthetic strategy includes both chemical and physical methods. Many of them have been shown that cellulose/ZnO composites have excellent antibacterial activity and are environment-friendly and have many applications for example food packing, antibacterial fibers and so on. This review mainly discusses the preparation methods of cellulose/ZnO and their effect on the morphology and properties.

Although zinc‐based batteries are promising candidates for eco‐friendly and cost‐effective energy storage devices, their performance is severely retarded by dendrite formation. As the simplest zinc compounds, zinc chalcogenides, and halides are individually applied as a Zn protection layer due to high zinc ion conductivity. However, the mixed‐anion compounds are not studied, which constrains the Zn2+ diffusion in single‐anion lattices to their own limits. A heteroanionic zinc ion conductor (ZnyO1−xFx) coating layer is designed by in situ growth method with tunable F content and thickness. Strengthened by F aliovalent doping, the Zn2+ conductivity is enhanced within the wurtzite motif for rapid lattice Zn migration. ZnyO1−xFx also affords zincophilic sites for oriented superficial Zn plating to suppress dendrite growth. Therefore, ZnyO1−xFx‐coated anode exhibits a low overpotential of 20.4 mV for 1000 h cycle life at a plating capacity of 1.0 mA h cm−2 during symmetrical cell test. The MnO2//Zn full battery further proves high stability of 169.7 mA h g−1 for 1000 cycles. This work may enlighten the mixed‐anion tuning for high‐performance Zn‐based energy storage devices.

Inorganic lead halide perovskite quantum dots (iLHP-QDs) have recently been used in the photocatalytic reaction. However, the factors that influence the photocatalytic performance of the iLHP-QDs have not been fully investigated. Herein, we synthesized a series of iLHP-QDs with varied halide ratios (CsPbX3, X = I, I0.67Br0.33, I0.5Br0.5, I0.33Br0.67, Br) and studied their influence on the photocatalytic performance by monitoring the polymerization of 2,2′,5′,2″-ter-3,4-ethylenedioxythiophene (TerEDOT). The CsPbI3 QDs showed the best performance owing to their narrow band gap and low exciton binding energy. Moreover, the photocatalytic performance of the iLHP-QDs could be simply improved by being treated with methyl acetate, which can be attributed to the replacement of the oleic acid by the short acetate acid and the introduction of the traps on the surface of QDs in the post-treatment. These results could help design a more efficient photocatalytic system and further promote the application of iLHP-QDs.

To explore the interactions of nanoparticles and bioresources and elucidate their effects on the morphology of the resulting composite, hierarchically structured cellulose@ZnO composites have been synthesized by an environmentally friendly hydrothermal method in one step. First, self-assembly induces the formation of hierarchical three-level structures, including cellulose/ZnO nanofibers, layers, and microfibers. Then, ZnO microparticles deposit onto the surface of the third-level cellulose/ZnO microfibers and accomplish the fabrication of a cellulose@ZnO composite, which eventually defines the hierarchical morphology of synthesized materials. The self-assembly mechanism was comprehensively examined. The electrostatic attraction between cellulose and ZnO, not hydrogen bonding, was found to be the main driving force for the formation of the first-level structure. A density functional theory study was conducted to support the self-assembly mechanism by optimizing the cellulose/ZnO structures at the molecular level, computing the corresponding thermodynamic energies and examining the spectroscopic properties. A hierarchically structured cellulose@ZnO composite is found to enhance the antibacterial activities. The diameters of the inhibition zone were found to be 48.8 and 45.5 mm against the Gram-positive bacterium Staphylococcus aureus (S. aureus) and the Gram-negative bacterium Escherichia coli (E. coli), respectively. This study is expected to improve food packaging materials while utilizing our newly synthesized cellulose@ZnO composite.

Hydrogen production from electrolyzed water plays an important role in clean energy system, but the current reported non‐noble metal catalysts still need to be paired with commercial Pt/C or RuO2 for overall water splitting. It is still a great challenge to develop high activity and stability bifunctional catalysts for both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in the same medium. To date, the emerging 2D MXenes have been extensively studied in the field of electrocatalysis because of their interesting surface physicochemical characteristics. However, the preparation process is very complex and difficult. Their intrinsic electrocatalytic properties are not good enough due to the disordered terminal groups (‐OH/‐F/‐Cl). Herein, the traditional preparation procedure is optimized, and the 2D layered compound Ta2CS2 is directly synthesized by a one‐step method. Unlike the typical MXenes with disorderly terminated groups, Ta2CS2 is terminated orderly with S atoms, and it shows excellent conductivity and electrochemical properties. Based on the great performance for OER and HER, the exfoliated Ta2CS2 (Ta2CS2‐E) is found to be an outstanding bifunctional catalyst of MXenes‐based materials for overall water splitting.

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Due to certain limitations of traditional models, the growth mechanism of porous anodic TiO 2 nanotubes has not been well determined currently. Herein, for the first time, a mathematical model of voltage-time transient curves under constant current conditions is derived theoretically, based on the conception of ionic and electronic currents and Ohm's law. The simulation results show high fidelity to the experimental curves, and illustrate the linear correlation between nanotube length and ionic current. Further, based on this model, the avalanche breakdown can be explained, which shows advantage over the former derivations on compact films. And this model indicates that the discrepancy between compact and porous oxide films lies on the magnitude of electronic current during anodization. Moreover, the proportion of the ionic and electronic current is then calculated during constant current anodization. It can be concluded that the ionic current contributes to the oxide growth while the electronic current gives rise to the oxygen bubble evolution which acts as the growth mould of the oxide. The present results promote the understanding of the growth kinetics of porous anodic oxides from qualitative interpretation to quantitative analyses.

Heterostructure construction, especially for anodes, is an effective strategy to promote electron transfer and improve surface reaction dynamics, thus achieving high performance in lithium ion batteries. Herein, in-situ partial conversion...