Since 2004, we have been developing nanomaterials with antimicrobial properties, the so-called nanoantimicrobials. When the coronavirus disease 2019 (COVID-19) emerged, we started investigating new and challenging routes to nanoantivirals. The two fields have some important points of contact. We would like to share with the readership our vision of the role a (nano)materials scientist can play in the fight against the COVID-19 pandemic. As researchers specifically working on surfaces and nanomaterials, in this letter we underline the importance of nanomaterial-based technological solutions in several aspects of the fight against the virus. While great resources are understandably being dedicated to treatment and diagnosis, more efforts could be dedicated to limit the virus spread. Increasing the efficacy of personal protection equipment, developing synergistic antiviral coatings, are only two of the cases discussed. This is not the first nor the last pandemic: our nanomaterials community may offer several technological solutions to challenge the ongoing and future global health emergencies. Readers' feedback and suggestions are warmly encouraged.

Last few decades, viruses are a real menace to human safety. Therefore, the rapid identification of viruses should be one of the best ways to prevent an outbreak and important implications for medical healthcare. The recent outbreak of coronavirus disease (COVID-19) is an infectious disease caused by a newly discovered coronavirus which belongs to the single-stranded, positive-strand RNA viruses. The pandemic dimension spread of COVID-19 poses a severe threat to the health and lives of seven billion people worldwide. There is a growing urgency worldwide to establish a point-of-care device for the rapid detection of COVID-19 to prevent subsequent secondary spread. Therefore, the need for sensitive, selective, and rapid diagnostic devices plays a vital role in selecting appropriate treatments and to prevent the epidemics. During the last decade, electrochemical biosensors have emerged as reliable analytical devices and represent a new promising tool for the detection of different pathogenic viruses. This review summarizes the state of the art of different virus detection with currently available electrochemical detection methods. Moreover, this review discusses different fabrication techniques, detection principles, and applications of various virus biosensors. Future research also looks at the use of electrochemical biosensors regarding a potential detection kit for the rapid identification of the COVID-19.

A thin Nafion-neodymium zirconium oxide nanotube (NdZr) composite (Nafion-NdZr) membrane has been fabricated and further modified by the polycation, poly­(diallyldimethylammonium chloride) (PDDA), and polyanion, poly­(sodium styrene sulfonate) (PSS). The ion selectivity of the Nafion-NdZr (1%)/[P-S]2 composite layer membrane was found to be 6.9, 3.5, and 2.3 times higher than those of recast Nafion, Nafion/[P-S]2 layer, and Nafion-NdZr (1%) composite membranes, respectively. As a result, the vanadium redox flow batteries (VFBs) assembled with Nafion-NdZr (1%) composite and Nafion-NdZr (1%)/[P-S]2 composite layer membranes have surpassed the VFB performance operated with recast Nafion and Nafion/[P-S]2 layer membranes. Noticeably, VFB operated with the Nafion-NdZr (1%)/[P-S]2 composite layer membrane (513.7 h) exhibited a longer self-discharge time than those with Nafion-NdZr (1%) (293.2 h), Nafion/[P-S]2 (124.1 h), and recast Nafion (32.7 h) membranes. Finally, the single VFB cell constructed with Nafion-NdZr (1%)/[P-S]2 and Nafion-NdZr (1%) membranes remarkably showed 80.1 and 73.4% capacity retention, respectively, over 200 charge–discharge cycles, whereas recast Nafion exhibited a 41.5% capacity retention over 100 cycles at a 40 mA cm–2 current density. The structure and morphology of the Nd2Zr2O7 nanotube, Nafion-NdZr composite, and Nafion-NdZr (1%)/[P-S]2 composite layer membranes were investigated by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared, and atomic force microscopy analyses. Longer cyclic performance and excellent oxidative, chemical, and thermal stability further prove the durability of proposed membranes.

Ce2Zr2O7 nanotube in SPAEK block copolymer enhance ion selectivity and VRFB performance. The self-discharge time of SPAEK/Ce2Zr2O7 membrane was higher than pristine SPAEK and NRE-212 membrane.

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The emerging problem of the antibiotic resistance development and the consequences that the health, food and other sectors face stimulate researchers to find safe and effective alternative methods to fight antimicrobial resistance (AMR) and biofilm formation. One of the most promising and efficient groups of materials known for robust antimicrobial performance is noble metal nanoparticles. Notably, silver nanoparticles (AgNPs) have been already widely investigated and applied as antimicrobial agents. However, it has been proposed to create synergistic composites, because pathogens can find their way to develop resistance against metal nanophases; therefore, it could be important to strengthen and secure their antipathogen potency. These complex materials are comprised of individual components with intrinsic antimicrobial action against a wide range of pathogens. One part consists of inorganic AgNPs, and the other, of active organic molecules with pronounced germicidal effects: both phases complement each other, and the effect might just be the sum of the individual effects, or it can be reinforced by the simultaneous application. Many organic molecules have been proposed as potential candidates and successfully united with inorganic counterparts: polysaccharides, with chitosan being the most used component; phenols and organic acids; and peptides and other agents of animal and synthetic origin. In this review, we overview the available literature and critically discuss the findings, including the mechanisms of action, efficacy and application of the silver-based synergistic antimicrobial composites. Hence, we provide a structured summary of the current state of the research direction and give an opinion on perspectives on the development of hybrid Ag-based nanoantimicrobials (NAMs).

A proton exchange membrane fuel cell uses perfluorosulfonic acid polymers as a proton exchange membrane but exhibits poor performance and durability under dry operating condition. Herein, we develop a composite membrane by incorporating porous inorganic filler, Zr 2 Gd 2 O 7 , into a perfluorosulfonic acid, Nafion. Zr 2 Gd 2 O 7 nanorods (ZrGdNR) are synthesized using an electrospinning process and subsequently calcination under air atmosphere at 500 °C. The Nafion-ZrGdNR composite (Nafion-ZrGdNR) and NRE-212 membranes exhibit power densities of 858 and 695 mW cm −2 , respectively, at 0.6 V under 100% relative humidity at 80 °C. At 20% relative humidity, the maximum power density of the Nafion-ZrGdNR membrane (448 mW cm −2 ) is 3.8 times higher than that of a commercial NRE-212 membrane (119 mW cm −2 ), and moreover, the Nafion-ZrGdNR membrane exhibits a fluoride emission rate of 6.9 × 10 −5 ppm h −1 cm −2 , which is about 240 times lower that of than the NRE-212 membrane (1670 × 10 −5 ppm h −1 cm −2 ) for 120 h of open-circuit voltage testing. The composite membrane shows high proton conductivity, superior oxidative stability, and improved mechanical strength. The outstanding performance and remarkable durability of the Nafion-ZrGdNR membrane are due to its efficient water diffusion and stability against hydroxyl radical attack, resulting in low ohmic resistance and improved membrane degradation.

One of the crucial challenges of our time is to effectively use metal and metal oxide nanoparticles (NPs) as an alternative way to combat drug-resistant infections. Metal and metal oxide NPs such as Ag, Ag2O, Cu, Cu2O, CuO, and ZnO have found their way against antimicrobial resistance. However, they also suffer from several limitations ranging from toxicity issues to resistance mechanisms by complex structures of bacterial communities, so-called biofilms. In this regard, scientists are urgently looking for convenient approaches to develop heterostructure synergistic nanocomposites which could overcome toxicity issues, enhance antimicrobial activity, improve thermal and mechanical stability, and increase shelf life. These nanocomposites provide a controlled release of bioactive substances into the surrounding medium, are cost effective, reproducible, and scalable for real life applications such as food additives, nanoantimicrobial coating in food technology, food preservation, optical limiters, the bio medical field, and wastewater treatment application. Naturally abundant and non-toxic Montmorillonite (MMT) is a novel support to accommodate NPs, due to its negative surface charge and control release of NPs and ions. At the time of this review, around 250 articles have been published focusing on the incorporation of Ag-, Cu-, and ZnO-based NPs into MMT support and thus furthering their introduction into polymer matrix composites dominantly used for antimicrobial application. Therefore, it is highly relevant to report a comprehensive review of Ag-, Cu-, and ZnO-modified MMT. This review provides a comprehensive overview of MMT-based nanoantimicrobials, particularly dealing with preparation methods, materials characterization, and mechanisms of action, antimicrobial activity on different bacterial strains, real life applications, and environmental and toxicity issues.