Abstract: The inventions relate to a process for making a platinum-free metal oxide/graphene catalyst by simultaneous reduction of a metal salt and a graphite oxide into a metal oxide and graphene for hydrogen production. The process includes (i) mixing the metal salt and the graphite oxide (GO) in water to form a metal salt-GO composite; and (ii) irradiating the metal salt-GO composite with focused solar light to spontaneously form the metal oxide/graphene catalyst.

Abstract: The invention relates to a composition in particle form having the structure: wherein M and M? are each independently a nutritionally relevant divalent metal and the particles are of a size between 1 micron and 1 nanometer. M and M? may be the same or different nutritionally relevant divalent metal selected from the group consisting of copper, zinc, manganese, iron, magnesium, and calcium. The particles may be made according to a process that includes application of microwave hydrothermal energy and/or ultrasonification.