Carboxymethyl cellulose assisted hydrothermal synthesis of litchi-like zinc ferrite nanoparticles for water remediation through visible photo-Fenton-like catalysis.

The conventional methods for the synthesis of zinc ferrite (ZnFe₂O₄) basically require high temperature calcination oxidation step, which produces environmentally unfriendly high energy consumption and may produce harmful gases that pollute the atmosphere, as well as the calcination synthesis limits the application of ZnFe₂O₄ such as preparation of organic composite materials. To end this, by adding carboxymethyl cellulose (CMC) to the reaction system, homogeneous litchi-like ZnFe₂O₄/CMC nanoparticles were successfully synthesized without alkali and calcination in this paper. The rich carboxyl group of CMC is conducive to the chelation and fixation of metal ions in the reaction precursor, which greatly promotes the synthesis of ZnFe₂O₄. The synthesized particle size is ~100 nm, with obvious ZnFe₂O₄ diffraction peaks and good crystallinity. The photocatalytic performance of the synthesized photocatalyst was evaluated by visible light-Fenton-like method. With the activation of peroxymonosulfate (PMS), 80.27 % of tetracycline hydrochloride (TC) was degraded in just 18 min, suggesting that the synthesized catalyst had an excellent photocatalytic performance. After four cycles, the catalyst still could degrade 64.52 % TC. And the same behavior in XRD and FTIR spectra confirms the stability of the photocatalyst. In addition, it was determined that singlet oxygen (¹O₂) dominated the visible light catalytic degradation.