AbstractThe objective of this work was to prepare a series of composite films (polysaccharides with LaFe0.8Cu0.2O3) for the degradation of methyl orange under ultraviolet irradiation. LaFe0.8Cu0.2O3 was prepared by a sol-gel method, and the composite films were obtained by cross-linking reactions between polysaccharides (xylan and chitosan) and LaFe0.8Cu0.2O3. Physical and chemical properties of the composite films were investigated by XRD, FTIR, SEM, and BET. Moreover, the influence of the weight ratio of polysaccharide to LaFe0.8Cu0.2O3 on the methyl orange degradation reaction was also studied. Results showed that 67% of the degradation efficiency was achieved within 480 min using chitosan/LaFe0.8Cu0.2O3 (2:1) as photocatalysts, while 58% was for xylan/LaFe0.8Cu0.2O3 (1:1). The difference was due to the variety in the structure of chitosan and xylan.