Raman spectra of the flow-synthesized HTs aged at 80 °C are shown in Figure . The spectra exhibit characteristic bands in the region of 100-600 cm -1 , which arise from M-O normal modes in the LDHs, and bands at 1040-1060 cm -1 assigned to CO3 2-stretches. Raman spectra of the hydrotalcites aged at 65 °C are similar to these aged at 80 °C and are shown in Figure in ESI.