The invention relates to a coating composition comprising an inorganic oxide precursor AMOx based on at least one inorganic element A selected from the group consisting of aluminum, silicium, titanium, zirconium, niobium, indium, tin, antimony, tantalum, and bismuth; and an inorganic oxide precursor BMOx based on at least one inorganic element B selected from the group consisting of scandium, yttrium, lanthanum, and the lanthanoids; wherein AMOx and BMOx are capable of forming a mixed inorganic oxide. A coating made from this composition shows enhanced resistance to hydrolysis. The invention also relates to a process for applying a coating on a substrate using such composition, more specifically to a liquid coating composition for use in a process of applying an anti-reflective coating on transparent substrate; to a coated substrate obtained with such process, and to an article, like a solar panel, comprising such coated substrate.