Development of a new zinc oxide/tin oxide/carbon xerogel photocatalyst for visible light photodegradation of 4-chlorophenol

Highlights: • SnO₂ and carbon xerogel addition modified the structural properties of the materials. • The ternary composite displayed enhanced photoactivity under visible radiation. • Chronoamperometry showed the improved charge separation on the ternary material. This paper reports the development of a new carbon xerogel/zinc oxide/tin oxide ternary photocatalyst and its application for the enhancement of photocatalytic response through the formation of heterojunctions composed of different phases. The results obtained from X-ray diffractometry showed that all the materials exhibited the hexagonal structure of zinc oxide. The application of infrared spectroscopy, energy dispersive spectroscopy and X-ray photoelectron spectroscopy (XPS) analyses helped confirm the presence of tin oxide and carbon xerogel in the photocatalytic material developed in the study. All the materials evaluated in the study showed photocatalytic activity under both solar and visible radiations. Under visible light, the optimized ternary material displayed higher photoactivity for 4-chlorophenol degradation, with total degradation of 55% in 5 h. The results obtained from chronoamperometry tests showed that the ternary composite exhibited the highest photocurrent among the samples evaluated when the materials were subjected to solar radiation.