Liao Yunlong, Tu Kaixiong, Han Xiaogang, Hu Liangbing, Connell John W, Chen Zhongfang, Lin Yi
National Institute of Aerospace, 100 Exploration Way, Hampton, VA, 23666, USA.
Department of Chemistry, Institute for Functional Nanomaterials, University of Puerto Rico, Rio Piedras Campus, San Juan, Puerto Rico, 00931, USA.
Sci Rep. 2015 Sep 29;5:14510. doi: 10.1038/srep14510.
Lateral surface etching of two-dimensional (2D) nanosheets results in holey 2D nanosheets that have abundant edge atoms. Recent reports on holey graphene showed that holey 2D nanosheets can outperform their intact counterparts in many potential applications such as energy storage, catalysis, sensing, transistors, and molecular transport/separation. From both fundamental and application perspectives, it is desirable to obtain holey 2D nanosheets with defined hole morphology and hole edge structures. This remains a great challenge for graphene and is little explored for other 2D nanomaterials. Here, a facile, controllable, and scalable method is reported to carve geometrically defined pit/hole shapes and edges on hexagonal boron nitride (h-BN) basal plane surfaces via oxidative etching in air using silver nanoparticles as catalysts. The etched h-BN was further purified and exfoliated into nanosheets that inherited the hole/edge structural motifs and, under certain conditions, possess altered optical bandgap properties likely induced by the enriched zigzag edge atoms. This method opens up an exciting approach to further explore the physical and chemical properties of hole- and edge-enriched boron nitride and other 2D nanosheets, paving the way toward applications that can take advantage of their unique structures and performance characteristics.
二维（2D）纳米片的侧面蚀刻会产生具有大量边缘原子的多孔二维纳米片。最近关于多孔石墨烯的报道表明，多孔二维纳米片在许多潜在应用中，如能量存储、催化、传感、晶体管以及分子传输/分离等方面，其性能优于完整的同类材料。从基础和应用的角度来看，获得具有明确孔形态和孔边缘结构的多孔二维纳米片是很有必要的。这对于石墨烯来说仍然是一个巨大的挑战，而对于其他二维纳米材料则很少有人探索。在此，报道了一种简便、可控且可扩展的方法，通过在空气中使用银纳米颗粒作为催化剂进行氧化蚀刻，在六方氮化硼（h-BN）基面表面刻蚀出几何形状明确的坑/孔形状和边缘。蚀刻后的h-BN进一步纯化并剥离成纳米片，这些纳米片继承了孔/边缘结构图案，并且在某些条件下，可能由于富集的锯齿形边缘原子而具有改变的光学带隙特性。这种方法为进一步探索富含孔和边缘的氮化硼以及其他二维纳米片的物理和化学性质开辟了一条令人兴奋的途径，为能够利用其独特结构和性能特征的应用铺平了道路。
