In this paper, surface analysis methods, including ζ-potential (Z_p) and cyclic voltammetry (CV), were utilized to obtain the photodegradation mechanism of dye mixture solutions. Firstly, nanostructured SrTiO₃ (STO) was prepared as photocatalyst, which is composed of 35–142 nm particles and with specific surface area of 56.90 m²/g. The highest dye degradation efficiency was obtained in the first 30 min of degradation, and enhanced degradation efficiency of methyl orange (MO) was observed in mixture solutions. CV results exhibit different oxidation potential values that demonstrate degraded accessibility under different pH conditions (original pH, 4.30, 2.40, 1.63). ζ-potential (Z_p) is measured at different pH values of unitary and binary solutions. Moreover, the influence factors in faintly acidic, neutral and strong acidic conditions are discussed. Kinetic and correlation between H⁺ and shift of ζ-potential are also studied.

本文利用ζ电位（Z _p）和循环伏安法（CV）等表面分析方法来研究染料混合物溶液的光降解机理。首先，制备了纳米结构的SrTiO ₃（STO）作为光催化剂，它由35–142 nm的颗粒组成，比表面积为56.90 m ² / g。在降解的前30分钟内获得最高的染料降解效率，并且在混合溶液中观察到甲基橙（MO）的降解效率提高。CV结果显示出不同的氧化电位值，这表明在不同的pH条件（原始pH，4.30、2.40、1.63）下可及性降低。ζ电位（Z _p）是在单一和二元溶液的不同pH值下测量的。此外，还讨论了在弱酸性，中性和强酸性条件下的影响因素。还研究了H ⁺与ζ电位位移之间的动力学和相关性。