en تخصصي Special Original articles <div style="text-align: justify;"><strong><em>Introduction:</em></strong> In this study, nanosized zero-valent zinc (Zn⁰) as a reducing agent, simultaneously synthesized and immobilized on an oxidizing agent, ZnO photocatalyst for degradation of methyl orange (MO) from the aqueous solution.<br> <strong><em>Materials and Methods:</em></strong> The prepared redox nanocomposite (nZn⁰-ZnO) was characterized by the XRD and SEM techniques. The prepared sample was separated by centrifuging. The preparation process of nZn⁰-ZnO including synthesis-immobilization, washing, and drying carried out under Argon gas flow. Moreover, the effect of temperature and kinetics reaction was studied.<br> <strong><em>Results:</em></strong> The results showed that degradation efficiency of prepared redox nanocomposite was increased compared to each ZnO nanopowder and Zn⁰ under the same operational condition. The calculated activation energy for the degradation process was 4.05 KJ.mol^-1. Finally, the results showed that the degradation processes followed pseudo first order kinetic model in the basic condition by the relative deviation modulus.<br> <strong><em>Conclusion:</em></strong> As compared to ZnO nanopowder and Zn⁰, the prepared redox nanocomposite showed high degradation efficiency for the removal of methyl orange from the aqueous solution.</div> Redox Nanocomposite, Methyl Orange Dye, Waste Water. 694 700 http://jehsd.ssu.ac.ir/browse.php?a_code=A-10-1-103&slc_lang=en&sid=1 Samira Taherkhani 0000-0002-9463-9280 No Department of Chemistry, Faculty of Science, University of Zanjan, Zanjan, Iran. Ali Khani a.khani59@yahoo.com 0000-0002-7997-1680 Yes Department of Chemistry and Chemical Engineering, Miyaneh Branch, Islamic Azad University, Miyaneh, Iran.