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This Review discusses how nanostructured materials are used to enhance the performances and safety requirements of Li batteries for hybrid and long-range electric vehicles. A significant amount of battery research and development is underway, both in academia and industry, to meet the demand for electric vehicle applications. When it comes to designing and fabricating electrode materials, nanotechnology-based approaches have demonstrated numerous benefits for improved energy and power density, cyclability and safety. In this Review, we offer an overview of nanostructured materials that are either already commercialized or close to commercialization for hybrid electric vehicle applications, as well as those under development with the potential to meet the requirements for long-range electric vehicles.

While the synthesis of hollow structures of transition metal oxides is well established, it is extremely challenging to fabricate complex hollow structures for mixed transition metal sulfides. Here we report an anion exchange method to synthesize a complex ternary metal sulfides hollow structure, namely nickel cobalt sulfide ball-in-ball hollow spheres. Uniform nickel cobalt glycerate solid spheres are first synthesized as the precursor and subsequently chemically transformed into nickel cobalt sulfide ball-in-ball hollow spheres. When used as electrode materials for electrochemical capacitors, these nickel cobalt sulfide hollow spheres deliver a specific capacitance of 1,036 F g −1 at a current density of 1.0 A g −1 . An asymmetric supercapacitor based on these ball-in-ball structures shows long-term cycling performance with a high energy density of 42.3 Wh kg −1 at a power density of 476 W kg −1 , suggesting their potential application in high-performance electrochemical capacitors. While the synthesis of hollow structures of transition metal oxides is well established, the related sulfide chemistry remains challenging. Here, the authors report the synthesis of nickel cobalt sulfide ball-in-ball hollow spheres, via anion exchange, and evaluate their pseudocapacitive behaviour.

Two-dimensional (2D) layered materials have attracted significant attention for device applications because of their unique structures and outstanding properties. Here, a field-effect transistor (FET) sensor device is fabricated based on 2D phosphorene nanosheets (PNSs). The PNS sensor exhibits an ultrahigh sensitivity to NO 2 in dry air and the sensitivity is dependent on its thickness. A maximum response is observed for 4.8-nm-thick PNS, with a sensitivity up to 190% at 20 parts per billion (p.p.b.) at room temperature. First-principles calculations combined with the statistical thermodynamics modelling predict that the adsorption density is ∼10 15  cm −2 for the 4.8-nm-thick PNS when exposed to 20 p.p.b. NO 2 at 300 K. Our sensitivity modelling further suggests that the dependence of sensitivity on the PNS thickness is dictated by the band gap for thinner sheets (<10 nm) and by the effective thickness on gas adsorption for thicker sheets (>10 nm). Phosphorene is one of a growing number of 2D materials with high potential for device applications. Here, the authors report a sensor composed of phosphorene nanosheets, showing a high sensitivity to NO 2 in dry air and also demonstrate that the sensitivity depends on the nanosheet thickness.

Regenerable nanozymes with high catalytic stability and sustainability are promising substitutes for naturally-occurring enzymes but are limited by insufficient and non-selective catalytic activities. Herein, we developed single-atom nanozymes of RhN 4 , VN 4 , and Fe-Cu-N 6 with catalytic activities surpassing natural enzymes. Notably, Rh/VN 4 preferably forms an Rh/V-O-N 4 active center to decrease reaction energy barriers and mediates a “two-sided oxygen-linked” reaction path, showing 4 and 5-fold higher affinities in peroxidase-like activity than the FeN 4 and natural horseradish peroxidase. Furthermore, RhN 4 presents a 20-fold improved affinity in the catalase-like activity compared to the natural catalase; Fe-Cu-N 6 displays selectivity towards the superoxide dismutase-like activity; VN 4 favors a 7-fold higher glutathione peroxidase-like activity than the natural glutathione peroxidase. Bioactive sutures with Rh/VN 4 show recyclable catalytic features without apparent decay in 1 month and accelerate the scalp healing from brain trauma by promoting the vascular endothelial growth factor, regulating the immune cells like macrophages, and diminishing inflammation. The catalytic activity of regenerable nanozymes is currently the bottle neck for their wider employment. Here, the authors report on single-atom nanozymes of RhN 4 , VN 4 , and Fe-Cu-N 6 with higher catalytic activities than natural enzymes, and demonstrate the Rh/VN 4 recyclability and scalp healing properties in bioactive sutures.

Interface confined reactions, which can modulate the bonding of reactants with catalytic centres and influence the rate of the mass transport from bulk solution, have emerged as a viable strategy for achieving highly stable and selective catalysis. Here we demonstrate that 1T′-enriched lithiated molybdenum disulfide is a highly powerful reducing agent, which can be exploited for the in-situ reduction of metal ions within the inner planes of lithiated molybdenum disulfide to form a zero valent metal-intercalated molybdenum disulfide. The confinement of platinum nanoparticles within the molybdenum disulfide layered structure leads to enhanced hydrogen evolution reaction activity and stability compared to catalysts dispersed on carbon support. In particular, the inner platinum surface is accessible to charged species like proton and metal ions, while blocking poisoning by larger sized pollutants or neutral molecules. This points a way forward for using bulk intercalated compounds for energy related applications. Interface confined reactions are a viable strategy for achieving stable and selective catalysts. Here, the authors demonstrate that 1T'-enriched lithiated MoS 2 can reduce metal ions in situ , forming zero valent platinum nanoparticle-intercalated MoS 2 , with enhanced hydrogen evolution activity.

The development of precision nanomedicines to direct nanostructure-based reagents into tumour-targeted areas remains a critical challenge in clinics. Chemical reaction-mediated localization in response to tumour environmental perturbations offers promising opportunities for rational design of effective nano-theranostics. Here, we present a unique microenvironment-sensitive strategy for localization of peptide-premodified upconversion nanocrystals (UCNs) within tumour areas. Upon tumour-specific cathepsin protease reactions, the cleavage of peptides induces covalent cross-linking between the exposed cysteine and 2-cyanobenzothiazole on neighbouring particles, thus triggering the accumulation of UCNs into tumour site. Such enzyme-triggered cross-linking of UCNs leads to enhanced upconversion emission upon 808 nm laser irradiation, and in turn amplifies the singlet oxygen generation from the photosensitizers attached on UCNs. Importantly, this design enables remarkable tumour inhibition through either intratumoral UCNs injection or intravenous injection of nanoparticles modified with the targeting ligand. Our strategy may provide a multimodality solution for effective molecular sensing and site-specific tumour treatment. Directing nanomedicines to desired locations - such as tumour sites - is difficult to achieve selectively. Here, the authors develop a method to covalently crosslink peptide-modified upconversion nanocrystals into tumour sites for photodynamic therapy and show in vivo tumour inhibition in mice.

Among the strategies used for enhancement of tumour retention of imaging agents or anticancer drugs is the rational design of probes that undergo a tumour-specific enzymatic reaction preventing them from being pumped out of the cell. Here, the anticancer agent olsalazine (Olsa) was conjugated to the cell-penetrating peptide RVRR. Taking advantage of a biologically compatible condensation reaction, single Olsa-RVRR molecules were self-assembled into large intracellular nanoparticles by the tumour-associated enzyme furin. Both Olsa-RVRR and Olsa nanoparticles were readily detected with chemical exchange saturation transfer magnetic resonance imaging by virtue of exchangeable Olsa hydroxyl protons. In vivo studies using HCT116 and LoVo murine xenografts showed that the OlsaCEST signal and anti-tumour therapeutic effect were 6.5- and 5.2-fold increased, respectively, compared to Olsa without RVRR, with an excellent ‘theranostic correlation’ (R2 = 0.97) between the imaging signal and therapeutic response (normalized tumour size). This furin-targeted, magnetic resonance imaging-detectable platform has potential for imaging tumour aggressiveness, drug accumulation and therapeutic response.

Nanocarriers (NCs) that can precisely deliver active agents, nutrients and genetic materials into plants will make crop agriculture more resilient to climate change and sustainable. As a research field, nano-agriculture is still developing, with significant scientific and societal barriers to overcome. In this Review, we argue that lessons can be learned from mammalian nanomedicine. In particular, it may be possible to enhance efficiency and efficacy by improving our understanding of how NC properties affect their interactions with plant surfaces and biomolecules, and their ability to carry and deliver cargo to specific locations. New tools are required to rapidly assess NC–plant interactions and to explore and verify the range of viable targeting approaches in plants. Elucidating these interactions can lead to the creation of computer-generated in silico models (digital twins) to predict the impact of different NC and plant properties, biological responses, and environmental conditions on the efficiency and efficacy of nanotechnology approaches. Finally, we highlight the need for nano-agriculture researchers and social scientists to converge in order to develop sustainable, safe and socially acceptable NCs. Nanocarrier delivery has huge potential in agriculture; however, there are significant scientific and societal barriers to overcome. In this Review, the authors explore the state of the field, what lessons can be learned from nanomedicine, and discuss what scientific and societal issues need to be addressed.

The abundance of plant-derived proteins, as well as their biodegradability and low environmental impact make them attractive polymeric feedstocks for next-generation functional materials to replace current petroleum-based systems. However, efforts to generate functional materials from plant-based proteins in a scalable manner have been hampered by the lack of efficient methods to induce and control their micro and nanoscale structure, key requirements for achieving advantageous material properties and tailoring their functionality. Here, we demonstrate a scalable approach for generating mechanically robust plant-based films on a metre-scale through controlled nanometre-scale self-assembly of water-insoluble plant proteins. The films produced using this method exhibit high optical transmittance, as well as robust mechanical properties comparable to engineering plastics. Furthermore, we demonstrate the ability to impart nano- and microscale patterning into such films through templating, leading to the formation of hydrophobic surfaces as well as structural colour by controlling the size of the patterned features. Green use of plant derived proteins in functional materials has been limited by inefficient methods to control micro and nanoscale structure. Here, the authors use nanoscale assembly of water-insoluble plant proteins to make meter scale films with comparable properties to conventional plastics.

Nanoscale plasma membrane curvature, generated in a controllable fashion by vertically aligned nanostructure arrays, promotes the accumulation of key endocytic proteins in live cells. Clathrin-mediated endocytosis (CME) involves nanoscale bending and inward budding of the plasma membrane, by which cells regulate both the distribution of membrane proteins and the entry of extracellular species 1 , 2 . Extensive studies have shown that CME proteins actively modulate the plasma membrane curvature 1 , 3 , 4 . However, the reciprocal regulation of how the plasma membrane curvature affects the activities of endocytic proteins is much less explored, despite studies suggesting that membrane curvature itself can trigger biochemical reactions 5 , 6 , 7 , 8 . This gap in our understanding is largely due to technical challenges in precisely controlling the membrane curvature in live cells. In this work, we use patterned nanostructures to generate well-defined membrane curvatures ranging from +50 nm to −500 nm radius of curvature. We find that the positively curved membranes are CME hotspots, and that key CME proteins, clathrin and dynamin, show a strong preference towards positive membrane curvatures with a radius <200 nm. Of ten CME-related proteins we examined, all show preferences for positively curved membrane. In contrast, other membrane-associated proteins and non-CME endocytic protein caveolin1 show no such curvature preference. Therefore, nanostructured substrates constitute a novel tool for investigating curvature-dependent processes in live cells.