Synthesis of crystalline ordered mesoporous CaO–ZrO 2 solid solution as a promising solid base

Abstract

The crystalline CaO–ZrO 2 mesoporous solid solution have been fabricated by a simple one-step procedure with zirconyl chloride octahydrate (ZrOCl 2·8H 2O) and calcium nitrate tetrahydrate (Ca(NO 3) 2·4H 2O) as metal precursors and triblock co-polymer of Pluronic P-123 as templating agent. Small-angle X-ray diffraction (SXRD) and transmission electron microscopy (TEM) results shows that ordered mesoporous structure and worm-like mesoporous structure were obtained when the molar ratio of Ca/Zr were 0.25 and 0.5. Wide angle X-ray diffraction (WXRD) and Raman spectra indicated that the formation of homogeneous solid solution was responsible for the stable cubic phase. All CaO–ZrO 2 solid solutions were endowed with strong basicity (H − = 9.3–12.2). The incorporation of Ca 2+ into ZrO 2 lattice led to the formation of solid solution structure and which could effectively improve the thermal stability and inhibit basic sites from leaching in the reaction.