Reactions of Persistent Carbenes with Hydrogen-Terminated Silicon Surfaces

Surface passivation has enabled the development of silicon-based solar cells and microelectronics. However, a number of emerging applications require a paradigm shift from passivation to functionalization, wherein surface functionality is installed proximal to the silicon surface. To address this need, we report here the use of persistent aminocarbenes to functionalize hydrogen-terminated silicon surfaces via Si–H insertion reactions. Through the use of model compounds (H–Si(TMS)3 and H–Si(OTMS)3), nanoparticles (H–SiNPs), and planar Si(111) wafers (H–Si(111)), we demonstrate that among different classes of persistent carbenes, the more electrophilic and nucleophilic ones, in particular, a cyclic (alkyl)(amino)carbene (CAAC) and an acyclic diaminocarbene (ADAC), are able to undergo insertion into Si–H bonds at the silicon surface, forming persistent C–Si linkages and simultaneously installing amine or aminal functionality in proximity to the surface. The CAAC (6) is particularly notable for its clean inse...