Hydrogen-bonded organic frameworks (HOFs) are a diverse and tunable class of materials, but their potential as free-standing two-dimensional nanomaterials has yet to be explored. Here we report the self-assembly of two layered hydrogen-bonded frameworks based on strong, charge-assisted hydrogen-bonding between carboxylate and amidinium groups. Ultrasound-assisted liquid exfoliation of both materials readily produces monolayer hydrogen-bonded organic nanosheets (HONs) with micron-sized lateral dimensions. The HONs show remarkable stability and maintain their extended crystallinity and monolayer structures even after being suspended in water at 80 °C for three days. These systems also exhibit efficient fluorescence quenching of an organic dye in organic solvents, superior to the quenching ability of the bulk frameworks. We anticipate that this approach will provide a route towards a diverse new family of molecular two-dimensional materials.

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通过电荷辅助氢键框架的液体剥离形成单层纳米片

氢键有机框架（HOF）是一类多样化且可调的材料，但它们作为独立二维纳米材料的潜力尚未被探索。在这里，我们报告了基于羧酸根和脒基团之间强的电荷辅助氢键的两层氢键框架的自组装。两种材料的超声波辅助液体剥离很容易产生横向尺寸为微米级的单层氢键有机纳米片（HON）。即使在 80°C 的水中悬浮三天后，HON 仍表现出卓越的稳定性，并保持其扩展的结晶度和单层结构。这些系统还表现出有机溶剂中有机染料的有效荧光猝灭，优于本体框架的猝灭能力。我们预计这种方法将为开发多种新的分子二维材料家族提供一条途径。