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• Ag@CN was prepared using a porous carbon nanocage for packaging Ag nanoparticles. • Porous carbon nanocages act as a "molecular grid" to protect the Ag nanoparticle and allow Cl− transport. • Ag@CN shows an excellent dichlorination capacity of 110.0 mg·g−1. • Ag@CN electrode decreased slightly by 7.14 % after 100 cycles at 10 mv s−1. Selective dechlorination is the key to solving the pollution problem of saline wastewater and achieving resource recovery, which is a major challenge for existing treatment methods. The recent development of capacitive deionization (CDI) based on the Ag@carbon electrode exhibits highly selective Cl− removal; however, its industrialization still poses a significant challenge due to the agglomeration and subsequent falling of Ag nanoparticles in the electrochemical field. In this work, we proposed a new physical confinement strategy based on carbon nanocage that can suppress the migration and agglomeration behavior of Ag nanoparticles. Firstly, a controllable construction of porous carbon nanocages on the surface of Ag nanoparticles was realized by the Ag+/H 2 O 2 synergistic oxidation-carbonization process, significantly inhibiting the migration and agglomeration of Ag nanoparticles in the Ag@carbon electrode. The Cl− removal capacity fluctuated around 110.0 mg·g−1 in 100 CDI cycles, exhibiting an excellent stability. Meanwhile, the high Cl−/SO 4 2− selectivity coefficient (89.0) promised the efficiently selective separation of Cl− ions from saline wastewater. In particular, the migration and agglomeration of Ag species in the carbon matrix was mainly attributed to the mutual attraction-recrystallization of Ag nanoparticles in the electrochemical field. Consequently, our study provides significant support for the industrial application of Ag@carbon electrodes and fundamentally solves the problem of saline wastewater pollution. [ABSTRACT FROM AUTHOR]

CoNi nanoparticle-decorated hollow carbon cubes (CoNi-HCCs) were synthesized using ZIF-67 as a sacrificial template. The synthesis utilizes the thermal instability of ZIF-67, creating hollow carbon nanostructures while facilitating carbonization and introducing metal nanoparticles (e.g., CoNi). Prototype Zn–air batteries equipped with CoNi-HCCs exhibited a promising discharge potential of 1.21 V and a charge potential of 2.04 V at 20 mA cm–2. These values are superior to those of Pt–Ru, whose discharge and charge potentials were 1.20 and 2.08 V, respectively. CoNi-HCCs also displayed a high peak power density of 159.6 mW cm–2, which is significantly higher than the value for Pt–Ru (120.2 mW cm–2). After 90 h of bifunctional cycling at 10 mA cm–2, CoNi-HCCs only experienced an efficiency loss of 3.4% and maintained 55.3% battery efficiency, much more durable than Pt–Ru (41.7% after only 60 h). [ABSTRACT FROM AUTHOR]

To improve the ductility of ultrafine-grained Al alloys, a simple and effective approach was developed to incorporate low-density ZrB 2 nanoparticles and high-density S′ precipitates into the 2024Al matrix through submerged FSP and subsequent aging. The resultant nanocomposite exhibits significant work-hardening, thereby achieving superior strength-ductility synergy during uniaxial tensile tests at room temperature. [ABSTRACT FROM AUTHOR]

Hybrids comprising hollow mesoporous nitrogen‐doped carbon (HMC) nanospheres and metal‐oxide nanoparticles were prepared through a hydrothermal synthesis. These materials exhibit excellent bifunctional catalytic activity in the oxygen reduction and evolution reactions (ORR and OER, respectively) that are core to the efficient operation of Zn‐air batteries. When incorporated into prototype devices, Co3O4 and MnCo2O4 nanoparticle‐decorated HMC exhibited discharge potentials of 1.26 and 1.28 V at 10 mA cm−2, respectively. 'CoFeNiO'‐decorated HMC exhibited a charging potential of 1.96 V at 10 mA cm−2. These metrics are far superior to benchmark Pt−Ru, which displayed discharge and charging potentials of 1.25 and 2.01 V, respectively, at the same current density. The battery equipped with Co3O4‐decorated HMC demonstrated 63 % initial efficiency before cycling. After cycling at 10 mA cm−2 for 100 hours, the battery efficiency was maintained at 56.5 %, outperforming the battery with Pt−Ru (50.2 % after 50 h). [ABSTRACT FROM AUTHOR]

Front Cover: Hollow Mesoporous Carbon Nanospheres Decorated with Metal Oxide Nanoparticles as Efficient Earth-Abundant Zinc-Air Battery Catalysts (ChemElectroChem 8/2021) Keywords: batteries; carbon; heterogeneous catalysis; nanoparticles; transition metals EN batteries carbon heterogeneous catalysis nanoparticles transition metals 1388 1388 1 04/30/21 20210412 NES 210412 B The Front Cover b shows an artistic representation of a new class of bifunctional zinc-air battery catalysts that consist of hollow mesoporous carbon nanospheres decorated with various precious-metal-free transition-metal oxide nanoparticles. Batteries, carbon, heterogeneous catalysis, nanoparticles, transition metals. [Extracted from the article]

A novel efficient adsorbent of bacterial cellulose/poly(m-phenylenediamine (BC/PmPD) was prepared for Cr(VI) removal by combining the advantages of high adsorption capacity of PmPD and easy reclamation of BC. Through monomer (mPD) pre-adsorption on BC, the stable hybrid structure of PmPD nanoparticles functionalization on BC fibril was successfully realized by in-situ oxidative polymerization of adsorbed mPD. The morphology and structure of the adsorbents were analyzed by SEM, TEM, XRD, FTIR, and XPS techniques. The interaction between BC and PmPD and adsorption mechanism were also analyzed. The optimized BC/PmPD has Langmuir Cr(VI) adsorption capacity of 434.78 mg/g, much higher than many reported adsorbents. The Cr(VI) adsorption on BC/PmPD was ascribed to the Cr(VI) adsorption on protonated NH and NH 2 groups and the redox reaction of Cr(VI) to Cr(III) by the reduction of amine, followed by Cr(III) chelation on imino groups of PmPD. The recycling test indicated that the BC/PmPD has good regeneration and reusability capacity with its fast-reversible macroscopic assembly and disassembly features, and high stabilization of PmPD on BC. Findings in the present study demonstrated that the BC/PmPD can be considered as a promising adsorbent for Cr(VI) removal due to its high adsorption capacity, efficient reclamation, good regeneration performance. [ABSTRACT FROM AUTHOR]