Two dimensional (2D) black phosphorus (BP) has attracted great attention in recent years, but its applications have been hindered by poor stability and difficulty in functionalization. In this work, we demonstrate that negatively charged BP fabricated via lithium ion intercalation exhibits much higher reactivity to diazonium modification than commonly studied neutral BP. The diazonium functionalized BP nanosheets show high surface coverage and remain stable under ambient conditions for more than 200 days. Such covalently modified BP nanosheets also provide a versatile platform for further chemical decoration toward a wide range of functionalities. As a proof of concept, we demonstrate that the highly stable and covalently functionalized 2D BP materials can be applied in nonlinear optics and catalysis. Together with the high versatility and scale-up potential, the surface functionalization method based on negatively charged 2D BP could significantly expand the applications of BP in a wide range of fields.

中文翻译：

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带负电的二维黑磷，可实现高效共价官能化†

近年来，二维（2D）黑磷（BP）引起了极大的关注，但是其应用受到稳定性差和功能化困难的困扰。在这项工作中，我们证明了通过与通常研究的中性BP相比，锂离子插层对重氮修饰具有更高的反应性。重氮官能化的BP纳米片表现出高的表面覆盖率，并在环境条件下保持稳定超过200天。此类共价改性的BP纳米片还提供了通用平台，可进一步实现多种功能的化学修饰。作为概念的证明，我们证明了高度稳定且具有共价功能的2D BP材料可用于非线性光学和催化。结合高通用性和规模化潜力，基于带负电荷的2D BP的表面功能化方法可以显着扩展BP在广泛领域中的应用。