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The emergence of metal‐organic frameworks (MOFs) provides a new platform of low‐cost and color‐saturated blue light‐emitting diodes ideal for display and solid‐state lighting applications. However, numerous established MOFs still exhibit weak deep‐blue‐light emission (<450 nm) owing to low energy/charge transfer efficiency. Here a pressure‐treated strategy to greatly enhance photoluminescence performance of deep‐blue light‐emitting Y(BTC)(H2O)6 (H3BTC: benzene‐1,3,5‐tricarboxylic acid) is reported. Pressure‐treated Y(BTC)(H2O)6 exhibits a bright emission at 409 nm with a photoluminescence quantum yield from the initial 2.8% increasing to 75.0%. The hydrogen bonding cooperativity effect increases hydrogen bond binding energy after pressure treatment and thus the planarization structure is locked. The increased electronic transition diversity and oscillator strength originating from the planarization structure are highly responsible for boosting metal‐to‐ligand charge transfer. The findings in this study provide significant insights into the underlying mechanism of the structure‐property relationship in Y(BTC)(H2O)6 and offer a promising strategy to harvest deep‐blue‐emitting MOFs materials. [ABSTRACT FROM AUTHOR]

Introducing nanostructures into diamonds is quite appealing for the synthesis of superhard materials with superior properties. However, as the grain size decreases to nanoscale, grain boundary effects become crucial yet complicated in the nanopolycrystalline diamond (NPD), making it challenging to tailor nanostructures. Here, atomistic simulations are combined with experiment to demonstrate a strengthening strategy for the sintered NPD by introducing thin amorphous grain boundary (AGB). The additive of small percentage of fullerene into precursors during sintering can significantly reduce crushed amorphous‐like nanodomains in diamond nanocrystals, leading to the formation of thin AGB. Such sintered NPD exhibits a significant hardness and fracture toughness enhancement, exceeding that of single crystal diamonds. These atomistic simulations show that upon straining the plastic deformation, crack initiation and propagation in NPD is AGB thickness dependent, and thin AGB can reduce crack nucleation and block crack propagation, well explaining the experimental observations. This study indicates that grain boundary modulation provides a promising approach for rational designs of high‐performance superhard materials with desired high strength. [ABSTRACT FROM AUTHOR]