A simple method to synthesize single-crystalline β-wollastonite nanowires

摘要

The single-crystalline β-wollastonite (β-CaSiO-3) nanowires were prepared via a simple hydrothermal method, in the absence of any template or surfactant using cheap and simple inorganic salts as raw materials. Xonotlite [Ca_6(Si_6O_(17))(OH)_2] nanowires were first obtained after hydrothermal treatment at a lower temperature of 200 ℃ for 24 h, and after being calcinated at 800 ℃ for 2 h, xonotlite nanowires completely transformed into β-wollastonite nanowires and the wire-like structure was preserved. The synthesized β-wollastonite nanowires had a diameter of 10-30nm, and a length up to tens of micrometers, and the single-crystalline monoclinic parawollastonite structured β-wollastonite was identified by XRD with the space group of P2_1/a and cell constants of α = 15.42 A, b = 7.325 A, c = 7.069 A and β = 95.38°. A possible growth mechanism of β-wollastonite nanowires was also proposed. The advantages of this method for the nanowire synthesis lie in the high yield, low temperature and mild reaction conditions, which will allow large-seale production at low cost.