Hierarchical dendritic micro-nano structure ZnFe

2

O

4

have been prepared by electrochemical reduction and thermal oxidation method in this work. X-ray diffractometry

Raman spectra and field-emission scanning electron microscopy were used to characterize the crystal structure

size and morphology. The results show that the sample (S-2) is composed of pure ZnFe

2

O

4

when the molar ratio of Zn

2+

/Fe

2+

in the electrolyte is 0.35. Decreasing the molar ratio of Zn

2+

/Fe

2+

the sample (S-1) is composed of ZnFe

2

O

4

and α-Fe

2

O

3

whereas increasing the molar ratio of Zn

2+

/Fe

2+

the sample (S-3) is composed of ZnFe

2

O

4

and ZnO. The lattice parameters of ZnFe

2

O

4

are influenced by the molar ratio of Zn

2+

/Fe

2+

:Zn at excess decreases the cell volume whereas Fe at excess increases the cell volume of ZnFe

2

O

4

. All the samples have the dendritic structure

of which S-2 has micron-sized lush branches with nano-sized le

aves. UV-Vis diffuse reflectance spectra were acquired by a spectrophotometer. The absorption edges gradually blue shift with the increase of the molar ratio of Zn

2+

/Fe

2+

. Photocatalytic activities for water splitting were investigated under Xe light irradiation in an aqueous olution containing 0.1 mol·L

-1

Na

2

S/0.02 mol·L

-1

Na

2

SO

3

in a glass reactor. The relatively highest photocatalytic activity with 1.41 μmol·h

-1

·0.02 g

-1

was achieved by pure ZnFe

2

O

4

sample (S-2). The photocatalytic activity of the mixture phase of ZnFe

2

O

4

and α-Fe

2

O

3

(S-1) is better than ZnFe

2

O

4

and ZnO (S-3).