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[Display omitted] • A self-supporting Ni/MnO 2 v/CC nanosheet array was obtained. • The obtained electrocatalyst exhibits excellent catalytic activity and stability. • Convincing AEM-LOM mechanism transformation has been identified. Birnessite (δ-MnO 2), inspired by biological photosynthesis, holds promise as oxygen evolution reaction (OER) catalysts in water electrolysis for clean energy. Given that Mn3+ serves as the active sites, various strategies have been employed to increase the Mn3+ content to boost the OER activity. To surpass the limitations of the traditional adsorbate evolution mechanism (AEM), we have adopted an electrochemical reduction method to introduce metallic Ni and enrich oxygen vacancies onto δ-MnO 2 nanosheets. The resulting Ni/MnO 2 v/CC exhibits exceptional OER performance, with a reduction in overpotential by 190 mV (from 478 mV to 289 mV) at 10 mA cm−2 and a Tafel slope as low as 45 mV dec-1, indicating accelerated catalytic activity. Experimental and theoretical analyses attribute this enhancement to a transition from the traditional AEM to lattice oxygen mechanism (LOM) mechanism. Moreover, the dual modification also enhances electronic conductivity, electrochemical surface area, and charge transfer ability of δ-MnO 2. Our work offers a pathway to overcome conventional limitations in OER electrocatalysts, applicable not only to Mn-based catalysts but also to a range of other transition metal oxides. [ABSTRACT FROM AUTHOR]

[Display omitted] • Migration regulation of Ca2+ species in the CaNaX zeolite was revealed in detail. • Utilization of hydroxylated Ca2+ species in the supercages of CaNaX zeolite was maximized via low-temperature calcination. • Remarkable CO 2 uptakes and selectivity on the 0.05CaNaX-250 zeolite were achieved. • This new sorbent displayed low heat of adsorption, fast kinetics and superior recyclability. • The formation of Ca(OH)+∙∙∙(CO 2) 2 adducts revealed by CO 2 -dosing FTIR experiments. Ca-FAU zeolite sorbents have been recognized as one of promising CO 2 capture materials, while it is subject to the change in the speciations and locations of Ca2+ species as adsorption sites in the FAU zeolite due to its susceptible migration. In this paper, a facile strategy is reported by tuning calcination temperatures and Ca loadings, to maximize the utilization of Ca2+ species in the supercages of CaNaX zeolites. Detail characterizations of TG-MS, in situ FTIR spectroscopy and XRD Rietveld refinement reveal the changeable regular in the chemical speciations, locations and number of Ca2+ species in the CaNaX zeolites. Synthetic 0.05CaNaX-250 zeolite (calcined at 250 °C and Ca loading of 1.58 wt%) guarantees at least 21 Ca(OH)+ species (depicted as hydroxylated Ca2+ species) in the supercages per FAU cell unit, close to theoretical value. Such sorbent apparently improves the CO 2 uptakes and the separation from CO 2 /N 2 and CO 2 /CH 4 , along with fast kinetics, low heat of adsorption, measured by dynamic and gravimetric adsorption methods, respectively. In addition, it keeps a superior recyclability after 10 times regeneration. CO 2 -dosing FTIR experiments further illustrate that excellent CO 2 adsorption performance are benefited from the formation of Ca(OH)+∙∙∙(CO 2) 2 adducts with an appropriate interaction. This work is of great significance to better understand the role of cations in FAU zeolites, and also provides an important reference value for the directional design of effective adsorption sites in other excellent CO 2 zeolite sorbents. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multifunctional BCN-based three-phase O/W CA-εPL PEs were constructed. • CA-εPL PEs into the structures of gelatin matrix to prepare GL-CA-εPL PE films. • GL-CA-εPL PE films showed excellent antioxidant, antibacterial properties, etc. • Cheese were packed in the GL-CA-εPL100 PE film extended shelf life. • GC-IMS showed samples no significant differences between packed film and unpacked. Owing to increasing plastic pollution and concerns about food safety, extensive research attention has been paid to biodegradable active packaging. Herein, we developed bacterial cellulose nanocrystal (BCN)-based three-phase Pickering nanoemulsion gelatin (GL) films. In detail, bacterial cellulose was obtained using Acetobacter xylinum , which was then hydrolyzed using sulfuric acid to prepare BCNs. Carnosic acid (CA) and ε-polylysine (εPL) were incorporated into the BCN matrix through electrostatic complexation and the matrix was ultrasonically triggered as an emulsification self-assembly strategy, forming the multifunctional BCN-based three-phase O/W Pickering nanoemulsions (CA-εPL PEs). Furthermore, a novel active packaging film (GL-CA-εPL PEs) was designed via intermolecular hydrogen bonding and dehydration condensation by introducing CA-εPL PEs into the 3D network structures of a GL matrix; both phases showed good interaction and compatibility, along with excellent antioxidant, antibacterial, UV-shielding, good mechanical, heat-sealing, sustainable release, and biodegradable properties. Additionally, fresh (acid-coagulated) and mozzarella cheese were packed in the GL-CA-εPL100 PE film, and their shelf life was extended due to delayed lipid peroxidation and inhibition of the growth of spoilage microorganisms. Sensorial and flavored (GC-IMS) analyses showed no significant differences between the samples packed in the GL-CA-εPL100 PE active film and the unpacked samples. This study provides scientific insights for designing BCN-based O/W multifunctional three-phase Pickering nanoemulsion delivery systems for active food packaging; the proposed method can be promising for reducing the environmental impact of plastic pollution. [ABSTRACT FROM AUTHOR]

• A novel A1-D-A2 type photocatalyst is designed for H 2 O 2 evolution. • The photocatalytic H 2 O 2 evolution activity is obviously enhanced. • Asymmetric receptor units induced efficient charge separation. • Dual reduction sites are confirmed to promote O 2 reduction to H 2 O 2. The study of hydrogen peroxide production by O 2 reduction reaction using covalent organic framework (COF) photocatalysts has attracted extensive attention in recent years. However, there are still great challenges in accurately controlling their structures to achieve rapid carrier separation and efficient O 2 reduction. Based on this, we constructed the A1-D-A2 COF photocatalytic material (TT-DTDA-COF) with asymmetric dual acceptor sites by connecting thieno [3,2-b] thiophene, benzene, and triazine as the basic units through imine bonds. Under the synergistic effect of thieno [3,2-b] thiophene and triazine electron acceptors, the separation and transfer efficiency of TT-DTDA-COF photogenerated carriers was significantly enhanced. At the same time, according to the in-situ infrared and DFT calculation results, it was found that these two acceptor units served as O 2 reduction sites, which realized the multi-site adsorption reduction of O 2 , and effectively enhanced the efficiency of photocatalytic O 2 reduction to H 2 O 2. The experimental results showed that the H 2 O 2 generation rate of TT-DTDA-COF with A1-D-A2 dual receptor structure was 1302 μmol·g−1·h−1 under visible light irradiation, which was 3.4 times higher than that of TB-DTDA-COF with single receptor D-A structure and higher than that of most of the materials reported so far. This study provides a new idea for accurately designing COF-based photocatalysts to achieve efficient O 2 reduction to produce H 2 O 2. [ABSTRACT FROM AUTHOR]

• DOX/IpYR achieved high penetration and long-term retention simultaneously. • DOX/IpYR regulated the expression of immune factors and PD-L1. • DOX/IpYR suppressed tumour growth and metastases. Conventional intratumoural drug delivery systems often struggle to achieve both high permeability and long-term retention. Smaller nanoparticles (NPs) readily diffuse into deep tumour regions, but their rapid clearance results in lower accumulation at tumour sites. Furthermore, although immunostimulatory molecules have been introduced for the immunotherapy of tumours, it is crucial to develop drug nanovehicles with immunomodulatory functions. Here, a novel self-assembled amphiphilic peptide, IpYR, self-assembled into spherical NPs after drug loading, which were transformed into nanofibres (NFs) with a high aspect ratio under the induction of alkaline phosphatase (ALP). This drug-loading system effectively prolonged the residence time of the chemotherapeutic drug in tumour tissues and displayed enhanced aggregation at tumour sites in vivo. Furthermore, the transformable peptide NPs not only inhibited tumour growth but also suppressed tumour metastasis. Importantly, the peptide nanovehicles inhibited the proliferation of Treg cells, downregulated the expression of immunosuppressive factors and PD-L1, and simultaneously stimulated the expression of immunogenic factors, effectively alleviating the immunosuppressive microenvironment. In conclusion, this transformable peptide-based nanodelivery system is a concise and promising nanoplatform for maintaining potent drug enrichment and inhibiting immunosuppression in the tumour microenvironment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Magnetic Fe 3 O 4 @MOF(M = Fe, Ti, Zr)@COFs were successfully fabricated. • Fe, Ti and Zr in MOF were investigated to reveal the influence on azo dye adsorption. • The Fe 3 O 4 @MOF(M = Fe, Ti, Zr)@COFs were used for adsorption of azo dyes in soft drinks with high capacities. • Adsorption mechanisms were systematically explored. Azo dyes in soft drinks present a serious risk to human health and are strictly limited in many countries. Herein, we demonstrate that covalent-organic framework (COF) can be facilely grown on magnetic metal–organic framework (MOF) to form three kinds of porous Fe 3 O 4 @MOF(M = Fe, Ti, Zr)@COFs composites for efficient azo dyes adsorption. Adsorption performances of Fe 3 O 4 @MOF(M = Fe, Ti, Zr)@COFs toward azo dyes were systemically investigated by adsorption kinetics, adsorption isotherms and adsorption thermodynamics. Under optimized conditions, the maximum adsorption capacities of both Fe 3 O 4 @MOF(Fe)@COF and Fe 3 O 4 @MOF(Zr)@COF for Congo red (CR) are 1250.02 and 625.13 mg g−1, and the Fe 3 O 4 @MOF(Ti)@COF for Chrysoidine (CYD) is 294.12 mg g−1, all which are higher than those of mostly previous reports. Furthermore, possible mechanisms of adsorption were revealed through Fourier-transform infrared spectra and X-ray photoelectron spectroscopy analysis. These Fe 3 O 4 @MOF(M = Fe, Ti, Zr)@COFs composites also present good biocompatibility, and exhibit high adsorption capacities for CR or CYD in soft drinks, which can be suggested as effective adsorbents for the azo dyes removal from soft drinks. [ABSTRACT FROM AUTHOR]

• Gallic acid serves as a green reducing agent to synthesize silver nanoparticles. • The photothermal conversion efficiency of GA-Ag NPs is as high as 48.7%. • GA-Ag NPs integrate photothermal effect with inherent antibacterial property. • GA-Ag NP hydrogel exhibits excellent broad-spectrum sterilization property. • Wound healing tests in vivo confirm the antibacterial effect and biocompatibility. Because of the indiscriminate use of antibiotics and threats of the drug resistance, bacterial wound infection remains one of the most difficult medical issues. Therefore, it is of great significance to develop novel antibacterial platforms. In this work, we successfully prepared gallic acid functional silver nanoparticles (GA-Ag NPs) by a one-pot method and then embedded them into the network structure of a biocompatible polysaccharide to obtain a novel hydrogel (GA-Ag NP hydrogel) with outstanding bactericidal effect. In this system, the embedded GA-Ag NPs not only act as an antibacterial agent sustainably released from the matrix of the hydrogel to realize sterilization, but also act as a photothermal agent that effectively and controllably converts 808 nm near-infrared ray light into heat to kill bacteria. In vitro testing verified the outstanding broad-spectrum sterilization property of the GA-Ag NP hydrogel against Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus). In vivo wound healing experiments confirmed the practical potential of this hydrogel in combating bacterial infections and accelerating wound healing. Hemolysis and cytotoxicity experiments showed that it has good biocompatibility. The development of this novel antibacterial hydrogel opens a new way to strengthen the antimicrobial arsenal for fighting bacterial infections. [ABSTRACT FROM AUTHOR]