Fig. 3: Synthetic mechanisms of the STT method.
From: Phase-selective synthesis and polymorphic transformation of crystalline red phosphorus
a Schematic diagram of the gas-phase molecule-mediated (GPM) solid-solid phase transition model. b, c Schematic illustration of the conventional CVT method and our system for transport rate control, respectively. d Photographs of quartz ampoules containing crystalline RP powders after the STT reactions with 0 to 24 hours holding time. e PXRD pattern of the crystalline RP powders obtained after the STT reaction with holding time ranging from 0 to 30 h. f UV-vis-NIR absorption spectra of crystalline RP powders with different holding time in (e), and (g) corresponding extracted optical bandgap distribution maps. h Schematic diagram of the continuous evolution of amorphous-Form II-Form IV-Form V with prolonged holding time.
