Synthesis and primary investigation of a novel inorganic gel based on calcium oxalate oligomers

Inspired by inorganic oligomers, we herein develop a novel inorganic gel based on calcium oxalate oligomers, and the crystallization morphology has been studied initially in this paper. The prepared oligomer is translucent gel and can exist stably in ethanol, but in aqueous medium it will change from gel to powder. In the crystallization process, because of the volatile speed of solvent and capping agent TEA at different temperature, CaC 2 O 4 oligomer gels (COOGs) exhibited distinct crystallization behavior and morphology. Compared with conventional inorganic crystallization, the crystallization process of the gel at room temperature shows a tendency to gradually extend to the inside of the gel. Moreover, the XRD pattern and SEM images shown that the COOGs achieved distinctly different crystal morphology under different temperature. These provide a preliminary research foundation for the crystallization behavior and control conditions of inorganic gels. Graphical abstract