Thermally stable hexagonal zirconium phosphate has been synthesized by a two-step method in which hexagonal zirconium sulfate surfactant composite is first produced by surfactant-assisted method and then subsequently treated in H3PO4 for long term. The 31P MAS NMR spectra show that the connectivity of phosphorus atoms increases from one ((Zr-O)PO 3) or two ((Zr-O)2PO2) to three ((Zr-O) 3PO) or four (P-O-P) upon calcination. There exists a significant number of surface Brönsted acid sites (Zr-O)3POH on calcined sample. The high thermal stability of hexagonal zirconium phosphate is due to (Zr-O)3PO and P-O-P connections, which build a network of zirconium phosphate.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering