The exponential increase in research focused on two-dimensional (2D) metal oxides has offered an unprecedented opportunity for their use in energy conversion and storage devices, especially for promising next-generation rechargeable batteries, such as lithium-ion batteries (LIBs) and sodium-ion batteries (NIBs), as well as some post-lithium batteries, including lithium-sulfur batteries, lithium-air batteries, etc. The introduction of well-designed 2D metal oxide nanomaterials into next-generation rechargeable batteries has significantly enhanced the performance of these energy-storage devices by providing higher chemically active interfaces, shortened ion-diffusion lengths, and improved in-plane carrier-/charge-transport kinetics, which have greatly promoted the development of nanotechnology and the practical application of rechargeable batteries. Here, the recent progress in the application of 2D metal oxide nanomaterials in a series of rechargeable LIBs, NIBs, and other post lithium-ion batteries is reviewed relatively comprehensively. Current opportunities and future challenges for the application of 2D nanomaterials in energy-storage devices to achieve high energy density, high power density, stable cyclability, etc. are summarized and outlined. It is believed that the integration of 2D metal oxide nanomaterials in these clean energy devices offers great opportunities to address challenges driven by increasing global energy demands.

progress in battery technology has been primarily driven by the specific demands of various applications. In the current era, a higher gravimetric/volumetric energy density is still an ever-growing requirement to power mobile electronics and extend the driving range of electric vehicles (EVs) with increased energy consumption. Meanwhile, the exploration and utilization of the various forms of renewable energy, such as wind, tidal, and solar energy, which are normally harvested as electricity but fluctuate greatly over time, require them to be stored, regulated, and then delivered for practical application. [1,2] As a result, these two issues impose high urgency and great necessity on the development of suitable battery systems to meet these demands, in particular, energy density, safety, and cost effectiveness. [3][4][5] At this stage, the most successfully commercialized secondary batteries are the LIBs, which have been widely applied in a variety of devices, including mobile phones, power tools, and electric vehicles. In an LIB, electricity is stored and released based on the reversible insertion-extraction of Li ions in the electrode materials. [6] The second-generation LIBs, which are based on layered LiNi x Mn y Co z O 2 (NMC) or LiNi 0.8 Co 0.15 Al 0.05 O 2 (NCA) cathode materials and graphite anode materials, normally have practical gravimetric/volumetric energy densities as high as 180-220 Wh kg −1 and have been applied in the latest electric vehicles (e.g., the Tesla Model S car) (Figure 1). Present mobile devices, transportation tools, and renewable energy technologies are more dependent on newly developed battery chemistries than ever before. Intrinsic properties, such as safety, high energy density, and cheapness, are the main objectives of rechargeable batteries that have driven their overall technological progress over the past several decades. Unfortunately, it is extremely hard to achieve all these merits simultaneously at present. Alternatively, exploration of the most suitable batteries to meet the specific requirements of an individual application tends to be a more reasonable and easier choice now and in the near future. Based on this concept, here, a range of promising alternatives to lithium-sulfur batteries that are constructed with non-Li metal anodes (e.g., Na, K, Mg, Ca, and Al) and sulfur cathodes are discussed. The systems governed by these new chemistries offer high versatility in meeting the specific requirements of various applications, which is directly linked with the broad choice in battery chemistries, materials, and systems. Herein, the operating principles, materials, and remaining issues for each targeted battery characteristics are comprehensively reviewed. By doing so, it is hoped that their design strategies are illustrated and light is shed on the future exploration of new metal-sulfur batteries and advanced materials. Metal-Sulfur BatteriesThe ORCID identification number(s) for the author(s) of this article can be found under https://doi.

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opens new doors for innovation in materials and sustainable technologies. Owing to the great diversity and complexity of nature, the well-evolved natural structures corresponding to specific functionalities may vary from 1D nanofibers or nanoneedles to 2D nanosheets or nanoplates or even 3D multiscale-ordered structures. [32] A good understanding of the structureproperty relationships is essential for the design and fabrication of bioinspired nanomaterials.2D nanomaterials have achieved some significant triumphs in various applications, benefitting from their unique structural characteristics and relevant chemical and physical properties. [33][34][35] In fact, 2D nanostructures also widely exist in nature and generate some amazing functionalities, which offers us great opportunities to further expand the design and fabrication of 2D nanostructured materials, devices, and technologies. [36] By integrating 2D nanomaterials with the bioinspired strategies, innovative materials and technologies have been proposed and realized. In this research news, recent progress that mainly achieved over the past decade in bioinspired materials and technologies based on 2D nanomaterials for targeted sustainable energy and environmental technologies, such as energy conversion and storages, environmental remediation, etc., is reviewed and discussed. As shown in Figure 1, three topical subjects, including bioinspired 2D photonic structures, bioinspired 2D energy nanomaterials, and bioinspired 2D superwetting materials, along with the challenges and opportunities will be the focus of this article, and give an overall perspective to this emerging and promising research area. Bioinspired 2D Photonic MaterialsTo survive in the wild world, natural species have evolved various unique structures with fascinating optical functionalities, such as glitzy structural colors for attracting prey or mates, [37] tunable camouflage colors for escaping from predators, [38] antireflection function of compound eyes for weak light vision, [36] and so on. These structures, as known as photonic crystal structures, have inspired the design of novel photonic micro/nanostructures and some smart optical devices.Among the various natural photonic structures, one class consists of periodically stacked 2D multilayers, also known as Bragg Stacks, have been found in many natural organisms, such as plants, insects, and marine benthos. [39] Multiple pairs of 2D layers with different refractive indexes in Bragg Stacks can generate iridescent structural colors through constructive The increasing demand for constructing ecological civilization and promoting socially sustainable development has encouraged scientists to develop bioinspired materials with required properties and functions. By bringing science and nature together, plenty of novel materials with extraordinary properties can be created by learning the best from natural species. In combination with the exceptional features of 2D nanomaterials, bioinspired 2D nanomaterials and technologies have delivered signif...