Photoelectrocatalytic degradation of deoxynivalenol on CuO-CuO/WO ternary film: Mechanism and reaction pathways.

A ternary film of CuO-CuO/WO possessing high visible-light photoelectrocatalytic (PEC) performance was prepared for degradation of deoxynivalenol (DON). In such a ternary film, the introduction of CuO-CuO significantly promoted the absorption of WO in the visible region and reduced the recombination of photogenerated charge carriers. As a result, the CuO-CuO/WO film exhibited high photoelectrochemical activity under visible light illumination. The PEC performance of CuO-CuO/WO film was evaluated by the decoloration of Rhodamine B. The result indicated that the CuO-CuO/WO film exhibited higher PEC activity than WO or CuO-CuO film. When the CuO-CuO/WO film was applied to study the removal of DON, the degradation efficiency reached 87.6% after 180-min PEC treatment. According to reactive oxygen species detected by electron spin resonance analysis, a Z-scheme and type-II PEC mechanism was proposed for this ternary film. Furthermore, the intermediates formed during the PEC degradation process of DON were separated by high-performance liquid chromatography and identified with liquid chromatography-mass spectrometry. On the basis of sixteen intermediate products identified, we proposed a degradation pathway for DON in such a PEC system.