Two-dimensional materials have emerged as an important research frontier for overcoming the challenges in nanoelectronics and for exploring new physics. Among them, black phosphorus, with a combination of a tunable bandgap and high mobility, is one of the most promising systems. In particular, black phosphorus nanoribbons show excellent electrostatic gate control, which can mitigate short-channel effects in nanoscale transistors. Controlled synthesis of black phosphorus nanoribbons, however, has remained an outstanding problem. Here we report large-area growth of black phosphorus nanoribbons directly on insulating substrates. We seed the chemical vapour transport growth with black phosphorus nanoparticles and obtain uniform, single-crystal nanoribbons oriented exclusively along the [100] crystal direction. With comprehensive structural calculations, we discover that self-passivation at the zigzag edges holds the key to the preferential one-dimensional growth. Field-effect transistors based on individual nanoribbons exhibit on/off ratios up to ~10⁴, confirming the good semiconducting behaviour of the nanoribbons. These results demonstrate the potential of black phosphorus nanoribbons for nanoelectronic devices and also provide a platform for investigating the exotic physics in black phosphorus.

二维材料已成为克服纳米电子学挑战和探索新物理学的重要研究前沿。其中，黑磷兼具可调谐带隙和高迁移率，是最有前途的系统之一。特别是，黑磷纳米带表现出优异的静电栅极控制能力，可以减轻纳米级晶体管中的短沟道效应。然而，黑磷纳米带的受控合成仍然是一个突出的问题。在这里，我们报告了直接在绝缘基板上大面积生长黑磷纳米带。我们用黑磷纳米颗粒进行化学气相传输生长，并获得仅沿[100]晶体方向取向的均匀单晶纳米带。通过全面的结构计算，我们发现锯齿形边缘的自钝化是优先一维生长的关键。基于单个纳米带的场效应晶体管表现出高达~10 ⁴的开/关比，证实了纳米带的良好半导体行为。这些结果证明了黑磷纳米带在纳米电子器件中的潜力，并为研究黑磷的奇异物理提供了平台。