Technologically controlling nanostructures is essential to tailoring the functionalities and properties of nanomaterials. Various methods free from lithography-based techniques have been employed to fabricate 2D nanostructures; however it is still hard to achieve a well interconnected 2D regular nanostructure. Here, we demonstrate a facile chemical solution method to self-assemble a regular and interconnected VO2 nanonet on the wafer scale. The nanonet shows a well-defined 2D truss network constructed by VO2 nanorods with twinning relationships. The growth direction and crystallographic orientation of nanorods are synchronously controlled, leading to horizontally epitaxial growth of nanorods along three symmetric directions of the (001) single-crystal sapphire substrate. The unique nanonets enable the acquisition of excellent resistance switching properties and dramatic fatigue endurance. A large resistance change of near 5 orders with a 1.7 °C width of the hysteresis loop is characterized comparably to the properties of single crystals without detectable degradation after 500 cycles over the metal-to-insulator transition. It indicates that the nanonet can serve as an exceptional candidate for practical application in switching functional devices. Our findings offer a novel pathway for self-assembly of 2D ordered nanostructures, which would provide new opportunities for the bottom-up integration of nanodevices.

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Nanopowders of nickel‐doped β‐silicon carbide (β‐SiC) with improved dielectric properties (compared with pure β‐SiC) were successfully produced using the mechanically activated self‐propagating high‐temperature synthesis method in an argon (Ar) atmosphere. The molar substitution of nickel (Ni) for silicon (Si) was 1%, 3%, and 5%. Powders of poly(tetrafluoroethylene) and ammonium chloride (NH4Cl) were used to promote the combustion reaction. The experimental results indicated an active role of Ni in the mechanism of combustion synthesis of SiC powders, which was reflected in the increase in combustion temperature and the velocity of propagation of the combustion wave, the microstructure of the produced nanopowders with a grain size of 100 nm for 5% Ni, and an improvement in the dielectric properties, specifically the increase in real (ɛ′) and imaginary parts (ɛ″) of the complex permittivity, in the frequency range of 8.2–12.4 GHz, compared with pure SiC. The X‐ray analysis of the produced powders suggests that Ni is accommodated in the lattice of SiC, which shrinks with increasing amounts of Ni.

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