Physicochemical and photocatalytic performance of the synthesized RuO2-ZnO photo-composite in the presence of pectinose solution

•A facile synthesis of RuO2-ZnO with different annealing temperatures usinpectinose solution.•RuO2-ZnO composite has a hexagonal wurtzite-type structure with three extra peaks related to the formation of RuO2 rutile phase.•The photocatalyst with different crystallite sizes and morphologies of RuO2-ZnO were obtained by increasing the annealing temperature.•The photodegradation percentage and rates of IC dye were reaching 99.9% with a rate of 36.38 × 10−3 min−1.