Fenton-like nanocatalyst for photodegradation of methylene blue under visible light activated by hybrid green DNSA@Chitosan@MnFe2O4

[Display omitted] •DNSA modified CS for the first time and acting as bridge between MB dye and MnFe2O4.•Excellent thermal stability achieved upon coating with MnFe2O4.•Hybrid DNSA@CS@MnFe2O4 exhibited adsorption and potent photodegradation towards MB under visible light with the aid of H2O2.•Hot filtration test proved the heterogeneity of reaction and good recyclability was attained with DNSA@CS@ MnFe2O4. High efficient 3,5-Dinitrosalicylic acid/Chitosan/MnFe2O4 (DNSA@CS@MnFe2O4) nano photocatalyst was prepared to enrich both adsorption and photodecomposition under visible light. This paper focused on the importance of DNSA@CS as an excellent connector between methylene blue (MB) and MnFe2O4 for accelerating photodegradation with the encouragement of photo-Fenton catalytic reagent hydrogen peroxide (H2O2). The optimum conditions were: contact time, 30 min, H2O2 concentration, 0.16 M, pH factor 9 and dosage 0.06 g/l at R.T, allowing excellent catalytic achievements 98.9% degree of decolorization in 30 min. More interestingly, the hybrid DNSA@CS@MnFe2O4 mechanism explained on the basis of coexistence of Mn2+/Mn3+ and Fe3+/Fe2+ redox couples during the reaction. The photocatalytic decolorization experimentally affirmed the suitability of DNSA@CS@MnFe2O4 obeying Langmuir-Hinshelwood model. Also, the nano-catalytic system was stable even after five runs. The prepared nanostructured catalyst provides simple fabrication to promote deep understand criteria for the mechanistic role of MnFe2O4 catalyst for degradation of MB molecules.