No abstract

2D nanomaterials are well suited for energy conversion and storage because of their thickness-dependent physical and chemical properties. However, current synthetic methods for translating 2D materials from the laboratory to industry cannot integrate both advantages of liquid-phase method (i.e., solution processibility, homogeneity, and massive production), and gas-phase method (i.e., high quality and large lateral size). Here, inspired by Chinese Sugar Figure Blowing Art, a rapid "gel-blowing" strategy is proposed for the mass production of 2D nonlayered nanosheets by thermally expanding the viscous gel precursors within a short time (≈1 min). A wide variety of 2D nanosheets including oxides, carbon, oxides/carbon and metal/carbon composites are synthesized on a large scale and with no impurities. Importantly, this method unifies the merits of both liquid-phase and gas-phase syntheses, giving rise to 2D products with high uniformity, nanometer thickness, and large lateral sizes (up to hundreds of micrometers) simultaneously. The success of this strategy highly relies on the speed of "blowing" and control of the amount of reactants. The as-synthesized nanosheet electrodes manifest excellent electrochemical performance for alkali-ion batteries and electrocatalysis. This method opens up a new avenue for economical and massive preparation of good-quality nonlayered 2D nanosheets for energy-related applications and beyond.

A new hollow yet hierarchical MOF structure is developed to construct robust Zn–Mn oxides@carbon hybrids with excellent lithium-ion storage properties.

For delivering the nanoscaled extraordinary characteristics in macroscopical bulk, it is essential to integrate two-dimensional nanosheets into threedimensional (3D) porous monoliths, alternatively called as 3D architectures, 3D networks, or aerogels. The intersupported structure of porous monolithic 3D graphene (3DG) can prevent aggregation or restacking of graphene individuals, and the interconnected sp 2 network of 3DG not only can provide the highway for the transport of electron/phonon but also can present continual cavities/channels for mass transfer. This review summarizes the synthesis methodology of 3DG porous monoliths and highlights the application for electric double-layer capacitors. Present challenges and future prospects about the manufacture and application of 3DG are also discussed.