Revealing the Br{\o}nsted-Evans-Polanyi Relation in Halide-Activated Fast MoS2 Growth Towards Millimeter-Sized 2D Crystals.

Achieving large-size two-dimensional (2D) crystals is key to fully exploiting their remarkable functionalities and application potentials. Chemical vapor deposition (CVD) growth of 2D semiconductors such as monolayer MoS2 has been reported to be activated by halide salts, yet clear identification of the underlying mechanism remains elusive. Here we provide unambiguous experimental evidence showing that the MoS2 growth dynamics are halogen-dependent through the Br{\o}nsted-Evans-Polanyi relation, based on which we build a growth model by considering MoS2 edge passivation by halogens, and theoretically reproduces the trend of our experimental observations. These mechanistic understandings enable us to further optimize the fast growth of MoS2 and reach record-large domain sizes that should facilitate practical applications.