硅烯（英语：Silicene）是一种类似于石墨烯的硅单质。尽管理论研究者推测存在这种物质并猜测了它的性质，研究者在十多年之后的2010年才观测到了具有这种结构的硅单质。

Silicene is a two-dimensional allotrope of silicon, with a hexagonal honeycomb structure similar to that of graphene. Contrary to graphene, silicene is not flat, but has a periodically buckled topology; the coupling between layers in silicene is much stronger than in multilayered graphene; and the oxidized form of silicene, 2D silica, has a very different chemical structure from graphene oxide.