Electrochemical performance of ZnMgO photoanodes prepared by a green synthesis route

Mesoporous ZnMgO nanopowders with varying Mg compositions (0 ≤ x ≤ 0.15) were synthesized via a green synthesis method using Psidium Guajava leaf extract. X-ray diffraction confirms a 10% solubility of Mg in ZnO and a preservation of the wurtzite phase. The 5% Mg doped ZnO sample shows a higher electrochemical performance with an electron lifetime of 35.63 µs and a phase angle of − 2.263° and correlated to the particle size, surface area, and the oxygen vacancy concentration, which is determined both from the phonon correlation length of the E 2 (high) Raman and the defect emission band measured from photoluminescence spectroscopy. Graphical abstract