Nucleophilic Attack Enables Chemical Suture of Crystalline Silicon at Room Temperature

Abstract Crystalline silicon (c-Si) has been widely used in semiconductor and energy-related industries. One of the biggest challenges of c-Si production is its high energy and environmental cost due to the requirement of high-temperature synthetic process and the accompanied intense greenhouse gas emission. Herein, we demonstrate a new process for preparing c-Si directly from hydride-terminated silicane (HSi) under mild conditions. We design a wet-chemistry approach that effectively creates Si-Si bonds between HSi flakes via nucleophilic attack by Lewis base reagent at room temperature. c-Si produced by such a chemical suturing process demonstrates promising capability in charge carrier migration and separation under visible light irradiation, which is of critical importance in photocatalysis. Compared to the existent c-Si manufacturing processes, the reported approach drastically reduces the energy consumption and provides a new strategy to tailor the electronic and photophysical properties of c-Si for optoelectronic and catalytic applications.