The chemical composition of quaternary metallic oxide coatings of the RuIrSnLa coated on Ti was investigated. The primary and secondary factors of effect of ingredients on behaviour and optimized formulation were presented by uniform design combined with partial least square (PLS) and grey relational degree analysis (GRD), as the indexes of investigation including service life, voltammetric charge, chlorine- evolution potential, oxygen-evolution potential, potential difference between the oxygen-evolution potential and chlorine-evolution potential. It was showed that Ir played the most important roles in improving service life of RuIrSnLa/Ti electrodes, and the next was Ru. And of all ingredients, La exerted the strongest influence on properties including electrocatalytic properties, the chlorine-evolution potential and the potential difference between the oxygen-evolution and chlorine-evolution. But the analysis of PLS regression suggested that La had negative effect on stability of the anodes. Sn was the main factor in increasing the oxygen-evolution potential. With the help of complementary advantages, the analysis of PLS and the grey relational degree can provide evidence for composition design and theoretical study of multicomponent oxide anodes.

Key words: metellic-oxide coating, rare earth La, uniform design, partial least square regression (PLS), grey relational analysis, electrochemical property