Importance of Solvent-Mediated Phenylsilane Decompositon Kinetics for High-Yield Solution-Phase Silicon Nanowire Synthesis

Large-scale supercritical fluid−liquid–solid (SFLS) silicon nanowire synthesis is demonstrated with a yield of >50 mg of nanowires in a single reaction in a 10 mL reactor. These large amounts of Si nanowires were enabled by the use of the aromatic solvents, benzene and toluene, which gave more than 50% atomic conversion of phenylsilane (MPS) to Si nanowires. In contrast, MPS conversion is only 1−5% when the reactions are carried out in hexane. MPS decomposes via homogeneous bimolecular disproportionation and the solvent (i.e., benzene) speeds MPS decomposition presumably by stabilizing the transition-state complex of the reaction.