Two-dimensional (2D) nanomaterials show unique electrical, mechanical, and catalytic performance owing to their ultrahigh surface-to-volume ratio and quantum confinement effects. However, ways to simply synthesize 2D metal oxide nanosheets through a general and facile method is still a big challenge. Herein, we report a generalized and facile strategy to synthesize large-size ultrathin 2D metal oxide nanosheets by using graphene oxide (GO) as a template in a wet-chemical system. Notably, the novel strategy mainly relies on accurately controlling the balance between heterogeneous growth and nucleation of metal oxides on the surface of GO, which is independent on the individual character of the metal elements. Therefore, ultrathin nanosheets of various metal oxides, including those from both main-group and transition elements, can be synthesized with large size. The ultrathin 2D metal oxide nanosheets also show controllable thickness and unique surface chemical state.

Ceramic materials exhibit very high stiffness and extraordinary strength, but they typically suffer from brittleness. Amorphization and size confinement are commonly used to reinforce materials. However, the inverse Hall–Petch effect and the shear-band softening effect usually limit further improvement of their performance under a critical size. With an optimum structure design, we demonstrate that dual-phase zirconia nanowires (DP-ZrO2 NWs) with nanocrystals embedded in an amorphous matrix as a strengthening phase can overcome these problems simultaneously. As a result of this structure, in situ tensile tests demonstrate that the mechanical properties have been enormously improved in a way that does not follow both the inverse Hall–Petch effect and the shear band softening effect. The elastic strain approaches ∼7%, and the ultimate strength is 3.52 GPa, accompanied by a high toughness of ∼151 MJ m–3, making the DP-ZrO2 NW composite the strongest and toughest ZrO2 ever achieved. The findings provide a way to improve the mechanical properties of ceramics in a controllable manner, which may serve as a pervasive approach to be broadly applied to a variety of materials.

wileyonlinelibrary.comfast-paced life. [ 22 ] For instance, although millions of miles of electrical cables have been used for providing electrical connections, the electrical energy produced from various physical or chemical sources to be distributed to users still need additional energy storage equipment, which causes unnecessary trouble and high cost. Moreover, people are possibly confronted with the inconvenience of sudden loss of power when using indoor electric appliances, and bothered by carrying heavy portable electronic accessories such as batteries and power cords simultaneously during a trip. Integrating the energy storage devices into appropriate energy transmission circuits should be an effective strategy to solve the problem of tiring energy distribution, sudden power off, and further lighten the weight of portable electronics, but current research barely involves the integration of energy storage devices and energy transit system, and these two systems still work independently with each other. [ 37,38 ] Supercapacitor, a promising class of energy storage device, is appealing because of its high power density, long cycle life time, and high energy effi ciency. [39][40][41][42][43][44][45][46][47][48][49][50][51][52][53][54] More importantly, supercapacitor can be easily fabricated in various confi gurations for ease of compatibility and integration with diversifi ed architectures of electronic devices. [55][56][57][58][59][60][61][62][63][64] From this, it can be expected that the integration of appropriate supercapacitor confi guration into proper circuit could achieve synchronous energy storage and energy transmission. Besides the confi guration, the exploration of naturally abundant and renewable biomaterials with high energy density for the new-generation green supercapacitors is intensively desired. [65][66][67][68][69] Thus, considering the issues of both the materials and confi guration, constructing an ideal integrated supercapacitor system based on renewable biomaterials for synchronous energy storage and transmission should be of scientifi c and technological importance due to their additional desirable economic, biocompatible and environmental friendly merits.Herein, we report the development of biocomposite-based fl exible integrated electrical cable for synchronous energy transmission and storage. In this unique integrated confi guration, the fi ber electrodes were alternately winded along the twisted electric wires, which worked not only as scaffolding to support and strengthen the slight electrodes but also as separators to spatially confi ne them to avoid short circuit ( Scheme 1 ). Distinct from the conventional electric wires used in a serial It becomes increasingly important to develop integrated systems with the aim of achieving maximum functionality for the state-of-the-art electronic devices. Here, a fl exible integrated electrical cable is reported by incorporating biomaterials based fi ber supercapacitors into a resistor-capacitor circuit. In this unique integrated confi gura...

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Conspectus Amorphous nanomaterials, with unique structural features such as long-range atomic disorder and nanoscale particle or grain sizes, possess some advantageous properties for a number of materials applications. For example, amorphous vanadium oxide exhibits a record-high cycling stability for supercapacitors. Several synthetic strategies have been developed to produce amorphous nanomaterials, such as physical processing-based approaches including cutting, deposition, and spinning, as well as chemical syntheses by solution or solid state reactions. However, despite the rapid development of amorphous nanomaterials, their morphology is still irregular or primarily sphere-like. The limited morphology control is partially attributed to the lack of preferred growth direction for the amorphous materials. It will be interesting to know whether different morphologies of even amorphous nanomaterials can influence their properties as much as their crystalline counterparts. Wet chemical synthesis, which can usually be carried out under relatively facile reaction conditions, has achieved remarkable success for creating crystalline nanomaterials with well-defined shapes, such as one-dimensional (1D) nanowires, two-dimensional (2D) nanosheets, and three-dimensional (3D) complex structures. However, there are two main obstacles for shape control of amorphous nanomaterials using wet chemical strategies. First, it is difficult to form a stable amorphous state under wet chemical conditions. The amorphous state is metastable in solution according to classic nucleation theory, which is prone to phase transformation to form crystalline state. Second, common morphology control mechanisms for nanocrystals are ultimately relying on the intrinsic directionality of the lattices, which unfortunately is not relevant to the isotropic amorphous nanomaterials. In this Account, we describe how shape control of 1D, 2D, and 3D amorphous nanomaterials can be achieved in wet chemical synthesis to create well-defined morphologies, which are based on two main strategies: Blocking agents that can stabilize the amorphous state in solution, and morphology-tunable parameters that can induce directional growth. Discussion on the phase transfer blocking mechanisms includes lattice disordering, controlled hydrolysis, rapid reaction, and ionic exchange, and for morphology control through confinement it includes precursor transformation, templated reactions, interfacial etching, and spatial confinement. In addition, we present examples showing how these well-defined morphology leads to desirable properties in applications of mechanics, energy storage, catalysis, and optics, highlighting their structural-properties relationship. Finally, some perspectives are discussed regarding future research opportunities in the area of amorphous nanomaterials.