Scanning Electron Microscopy -Energy Dispersive X-ray (SEM-EDX). SEM images and chemical composition from EDX were acquired using a TESCAN MIRA3 FEG-SEM equipped with an Oxford Instruments X-maxN 80 EDX detector. SEM images were acquired at 5kV and EDX spectra at 10kV. Thermogravimetric Analysis (TGA). Spectra were recorded on TGA/DSC 2 from Mettler Toledo. Samples of typically 20 mg were placed in CC21 Cylindrical Alumina Crucible and heated from 25 to 900 °C at 5 °C /min, under flowing N2 atmosphere.