“…Two-dimensional (2D) semiconductor materials, such as graphene [ 1 , 2 ], MoS 2 [ 3 , 4 ], WSe 2 [ 5 ], WS 2 [ 6 ], MoTe 2 [ 7 , 8 ], SnSe 2 [ 9 ], and black phosphorous (BP) [ 10 – 18 ], have been widely studied for the potential applications in the next generation devices including field emitters [ 10 – 12 ], gas sensors [ 13 , 14 ], solar cells [ 17 ], field-effect transistors [ 18 ], optoelectronics [ 19 ], and light-emitting diodes [ 20 ]. Among these 2D materials, BP is found to be more thermodynamically stable under the ambient conditions [ 14 ].…”