References
   -  R. Rahimi, H. Kerdari, M. Rabbani, M. Shafiee, Synthesis,
	   characterization and adsorbing properties of hollow Zn-Fe2O4
    nanospheres on removal of Congo red from aqueous solution,
    Desalination, 280 (2011) 412–418. 
 
  -  Y. Wang, F. Liu, Q. Yang, Y. Gao, P. Sun, T. Zhang, G. Lu,
    Mesoporous ZnFe2O4 prepared through hard template and its
    acetone sensing properties, Mater. Lett., 183 (2016) 378–381. 
 
	-  T. Mathe, T. Moyo, J. Msomi, Optical properties of Zn0.5
		(Ni, Co)0.5 Fe2O4 mixed spinel ferrite thin films, Phys. Status
    Solidi C, 5 (2008) 591–593. 
 
  -  A.A. Hossain, H. Tabata, T. Kawai, Magnetoresistive properties
	  of Zn1−xCoxFe2O4 ferrites, J. Magn. Magn. Mater., 320 (2008)
    1157–1162. 
 
  -  J. Yan, S. Gao, C. Wang, B. Chai, J. Li, G. Song, S. Chen,
    A facile electrospinning and direct annealing method for the
    fabrication of multi-porous ZnFe2O4 nanotubes with enhanced
    photocatalytic activity, Mater. Lett., 184 (2016) 43–46. 
 
  -  M. Zhao, S. Fan, J. Liang, Y. Liu, Y. Li, J. Chen, S. Chen, Synthesis
    of mesoporous grooved ZnFe2O4 nanobelts as peroxidase
    mimetics for improved enzymatic biosensor, Ceram. Int., 41
    (2015) 10400–10405. 
 
  -  L. Fan, Y. Zhou, W. Yang, G. Chen, F. Yang, Electrochemical
    degradation of aqueous solution of Amaranth azo dye on ACF
    under potentiostatic model, Dyes Pigm., 76 (2008) 440–446. 
 
  -  M. Rabbani, M. Heidari-Golafzani, R. Rahimi, Synthesis
    of TCPP/ZnFe2O4@ZnO nanohollow sphere composite for
    degradation of methylene blue and 4-nitrophenol under visible
    light, Mater. Chem. Phys., 179 (2016) 35–41. 
 
	-  E. Oguz, B. Keskinler, Comparison among O3, PAC adsorption,
		O3/HCO3−, O3/H2O2 and O3/PAC processes for the removal of
    Bomaplex Red CR-L dye from aqueous solution, Dyes Pigm., 74
    (2007) 329–334. 
 
  -  J.C. Lopez-Montilla, S. Pandey, D.O. Shah, O.D. Crisalle,
    Removal of non-ionic organic pollutants from water via liquid–
    liquid extraction, Water Res., 39 (2005) 1907–1913. 
 
  -  S. Kumar, R.R. Nair, P.B. Pillai, S.N. Gupta, M. Iyengar, A. Sood,
    Graphene oxide–MnFe2O4 magnetic nanohybrids for efficient
    removal of lead and arsenic from water, ACS Appl. Mater.
    Interfaces, 6 (2014) 17426–17436. 
 
  -  C. Wu, J. Tu, C. Tian, J. Geng, Z. Lin, Z. Dang, Defective
    magnesium ferrite nano-platelets for the adsorption of As(V):
    the role of surface hydroxyl groups, Environ. Pollut., 235 (2018)
    11–19. 
 
  -  Z. Jia, Q. Qin, J. Liu, H. Shi, X. Zhang, R. Hu, S. Li, R. Zhu,
    The synthesis of hierarchical ZnFe2O4 architecture and their
    application for Cr(VI) adsorption removal from aqueous
    solution, Superlattices Microstruct., 82 (2015) 174–187. 
 
  -  C.L. Warner, W. Chouyyok, K.E. Mackie, D. Neiner, L.V. Saraf,
    T.C. Droubay, M.G. Warner, R.S. Addleman, Manganese
    doping of magnetic iron oxide nanoparticles: tailoring surface
    reactivity for a regenerable heavy metal sorbent, Langmuir, 28
    (2012) 3931–3937. 
 
  -  Y.J. Tu, T.S. Chan, H.W. Tu, S.L. Wang, C.F. You, C.K. Chang,
    Rapid and efficient removal/recovery of molybdenum onto
    ZnFe2O4 nanoparticles, Chemosphere, 148 (2016) 452–458. 
 
  -  J. Li, D.H. Ng, P. Song, Y. Song, C. Kong, Bio-inspired synthesis
    and characterization of mesoporous ZnFe2O4 hollow fibers with
    enhancement of adsorption capacity for acid dye, J. Ind. Eng.
    Chem., 23 (2015) 290–298. 
 
  -  M. Sun, Y. Chen, G. Tian, A. Wu, H. Yan, H. Fu, Stable
    mesoporous ZnFe2O4 as an efficient electrocatalyst for hydrogen
    evolution reaction, Electrochim. Acta, 190 (2016) 186–192. 
 
  -  D. Gherca, R.G. Ciocarlan, D.G. Cozma, N. Cornei, V. Nica,
    I. Sandu, A. Pui, Influence of surfactant concentration
    (carboxymethylcellulose) on morphology and particle sizes of
    cobalt nanoferrites, Struc., Rev. Chim., 14 (2013) 15. 
 
  -  L. Hou, H. Hua, L. Lian, H. Cao, S. Zhu, C. Yuan, Green templatefree
    synthesis of hierarchical shuttle-shaped mesoporous
    ZnFe2O4 microrods with enhanced lithium storage for advanced
    Li-ion batteries, Chem. Eur. J., 21 (2015) 13012–13019. 
 
  -  X.B. Zhong, Z.Z. Yang, H.Y. Wang, L. Lu, B. Jin, M. Zha,
    Q.C. Jiang, A novel approach to facilely synthesize mesoporous
    ZnFe2O4 nanorods for lithium ion batteries, J. Power Sources,
    306 (2016) 718–723. 
 
  -  M. Su, C. He, V.K. Sharma, M.A. Asi, D. Xia, X.-z. Li, H. Deng,
    Y. Xiong, Mesoporous zinc ferrite: synthesis, characterization,
	  and photocatalytic activity with H2O2/visible light, J. Hazard.
    Mater., 211 (2012) 95–103. 
 
  -  R. Rameshbabu, R. Ramesh, S. Kanagesan, A. Karthigeyan,
    S. Ponnusamy, Synthesis of superparamagnetic ZnFe2O4 nanoparticle by surfactant assisted hydrothermal method,
    J. Mater. Sci.: Mater. Electron., 24 (2013) 4279–4283. 
 
  -  S.-H. Yu, T. Fujino, M. Yoshimura, Hydrothermal synthesis of
    ZnFe2O4 ultrafine particles with high magnetization, J. Magn.
    Magn. Mater., 256 (2003) 420–424. 
 
  -  W. Shi, F. Guo, H. Wang, C. Liu, Y. Fu, S. Yuan, H. Huang, Y. Liu,
    Z. Kang, Carbon dots decorated magnetic ZnFe2O4 nanoparticles
    with enhanced adsorption capacity for the removal of dye from
    aqueous solution, Appl. Surf. Sci., 433 (2018) 790–797. 
 
  -  C. Muntean, M. Stoia, P. Barvinschi, Synthesis of nanocrystalline
    ZnFe2O4 and its use for the removal of Congo Red from aqueous
    solutions, Environ. Eng. Manage. J., 12 (2013) 959–967. 
 
  -  R. Rahimi, M. Heidari-Golafzani, M. Rabbani, Preparation
    and photocatalytic application of ZnFe2O4@ZnO core–shell
	  nanostructures, Superlattices Microstruct., 85 (2015) 497–503.