标题： 自下而上生长石墨烯纳米刺和纳米带 显示英文标题

标题： Bottom-up Growth of Graphene Nanospears and Nanoribbons

摘要： 石墨烯纳米带（GNRs）被认为是下一代电子学中最具有前景的材料之一，然而一种可靠且可控的合成方法仍然缺乏。 在此，我们报道了在铜表面通过化学气相沉积法（CVD）生长GNRs及其相应的生长机制。 一维GNR的生长是通过液态催化剂颗粒在表面上的传播引导的气-液-固（VLS）石墨烯生长实现的。 通过调节生长过程中H2的流量来控制沿GNR宽度方向的气-固-固（VSS）石墨烯生长的抑制，从而形成我们称之为石墨烯纳米矛（GNSs）的形似梭镖的石墨烯。 实时的视觉和空间分辨观察证实了石墨烯的VSS生长可以被完全抑制，并在铜表面导致GNR的形成。 这些发现揭示了石墨烯生长机制的关键见解，并为实现一种简便且可扩展的自由站立GNRs合成方法打开了大门。 显示英文摘要

摘要： Graphene nanoribbons (GNRs) are considered one of the most promising materials for next generation electronics, however a reliable and controllable synthesis method is still lacking. Here, we report the CVD growth of GNRs on a copper surface and the corresponding mechanisms of growth. One-dimensional GNR growth is enabled by a vapor-liquid-solid (VLS) graphene growth guided by on-surface propagation of a liquid catalyst particle. Controlling the suppression of vapor-solid-solid (VSS) graphene growth along the width direction of the GNR by tuning the flow of H2 during growth gives rise to a spear head-shaped graphene that we term graphene nanospears (GNSs). The real-time visual and spatially resolved observations confirm the VSS growth of graphene can be fully suppressed and lead to GNR formation on Cu surface. These findings reveal key insight into the growth mechanism of graphene and open a door for achieving a facile and scalable method of synthesizing free standing GNRs.