Metal Oxide Based Hydroelectric Cell for Electricity Generation by Water Molecule Dissociation without Electrolyte/Acid

Never before has electricity been generated out of metal oxides without using any light (UV/IR), acid, or alkali, but it has been achieved by adding a few drops of water on nanoporous metal oxide based Hydroelectric cell (HEC) at room temperature. Electricity generation has been validated and unified for six different metal oxides based on the principle of water dissociation at oxygen deficient nonporous pellet. The presence of oxygen vacancies on the surface of all metal oxide samples has been confirmed by Raman and Photoluminescence spectroscopy techniques. Tin oxide (SnO2) based HEC has delivered maximum power similar to 16.6 mW in a 4.48 cm(2) cell area with highest current 22.2 mA, approximately 2.075 times higher than reported 8 mA current in ferrite based HEC. Water chemidissociation at metal oxide surface was found to be reinforced predominantly by electronegativity of metal cations and oxygen vacancies on nanoporous surface. Divergent peak current values ranging from 22.2 to 1.1 mA were obtained depending on internal resistance, grain boundary nature, water molecule dissociation capability, and nanopores connectivity in different oxides. Slow diffusion of ions in certain metal oxides due to high impedance of grain boundaries has reduced current as confirmed by dielectric and impedance spectroscopy. Metal oxide HEC provides an ecofriendly, cost-effective, and portable green energy source with almost no running cost.