New Advances into Nanostructured Oxides.

Inorganic nanostructured (metal) oxides are a large class of inorganic materials extensively investigated for their unique and outstanding properties that allow for their use within a multitude of technological fields of emerging interest, such as (photo)catalysis, environmental remediation processes, energy storage, controlled transport and/or release of drugs and chemicals, biomedicine, sensing, development of smart materials, stimuli-responsive materials, and nanocomposites [[1], [3], [5]]. Iridium oxide is a very peculiar (metal) oxide as it is characterized by showing metallic-type conductivity and also displaying a low surface work function (which is the energy required for moving an electron from the Fermi level to the local vacuum level), high chemical stability, and good stability under the influence of high electric fields. Experimental results showed that: (i) the optimum adsorption pH for all systems is pH 2-4, (ii) the Freundlich isotherm model fitted the experimental data (mainly physisorption), (iii) the maximum adsorption capacity at optimized conditions was registered by zirconium oxide (73 mg/g), followed by cerium oxide and titania. The commercial (metal) oxides investigated were: silica, titania, zirconium oxide, cerium oxide, tin oxide, and mixed systems, such as an aluminosilicate, cerium aluminum oxide, aluminum titanium oxide, and cerium zirconium oxide. [Extracted from the article]