Modifying of Nanostructured MnWO4 by Ca-, Cu- and Co-Doping towards Artificial Photosynthesis Applications

Nowadays, the human societies encountered some serious environmental problems because of population growth and industrialization. One of them is increasing the amount of CO2 in the atmosphere [1]. It has been shown that during natural photosynthesis water oxidation happens on the surface of a Mn-Ca oxide complex and produced proton travels to another site which CO2 reduction occurs on it [2, 3].In this study, we prepared nanostructured manganese tungstate by reflux method and modified it by doping with Ca+2, Co+2 and Cu+2 ions. The morphology and crystal structure of prepared materials were investigated by TEM and XRD techniques, respectively. The specific surface area of prepared samples were determined using BET and their bandgaps were determined with a combination of DRS and electrochemical impedance spectroscopy. Finally, their abilities towards electrochemical water splitting and CO2 reduction were investigated by linear sweep voltammetry