Hydrothermal derived nitrogen doped SrTiO3 for efficient visible light driven photocatalytic reduction of chromium(VI)

Guanjie Xing,Xiaojing Wang,Tao Sun,Yiguo Su,Lanxiao Zhao

doi:10.1186/s40064-016-2804-2

Abstract

In this work, we report on the synthesis of nitrogen doped SrTiO3 nanoparticles with efficient visible light driven photocatalytic activity toward Cr(VI) by the solvothermal method. The samples are carefully characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, UV–Vis diffuse reflectance spectroscopy and photocatalytic test. It is found that nitrogen doping in SrTiO3 lattice led to an apparent lattice expansion, particle size reduction as well as subsequent increase of Brunner–Emmet–Teller surface area. The visible light absorption edge and intensity can be modulated by nitrogen doping content, which absorption edge extends to about 600 nm. Moreover, nitrogen doping can not only modulate the visible light absorption feature, but also have consequence on the enhancement of charge separation efficiency, which can promote the photocatalytic activity. With well controlled particle size, Brunner–Emmet–Teller surface area, and electronic structure via nitrogen doping, the photocatalytic performance toward Cr(VI) reduction of nitrogen doped SrTiO3 was optimized at initial hexamethylenetetramine content of 2.Electronic supplementary materialThe online version of this article (doi:10.1186/s40064-016-2804-2) contains supplementary material, which is available to authorized users.

Highlights

Hexavalent chromium (Cr(VI)) is a common pollutant detected in groundwater originated from excessively released of electroplating, pigment production and tanning of leather, etc. (Wang et al 2013a)
There were no peaks belonging to Transmission electron microscopy (TEM) was employed for samples morphology and crystal structure
It can be seen that pure SrTiO3 exhibited irregular cubic-like morphology with an average diameter of about 200 nm, which is larger than that obtained from X-ray power diffraction (XRD) results

Summary

Introduction

Hexavalent chromium (Cr(VI)) is a common pollutant detected in groundwater originated from excessively released of electroplating, pigment production and tanning of leather, etc. (Wang et al 2013a). As for nitrogen doped samples, the diameter of N-SrTiO3(2) showed a particle size reduction to ~100 nm with the same cubic-like morphology (Fig. 2c). The UV–Vis absorption performance of the samples was employed to investigate the electronic transitions and band gap energies of nitrogen doped SrTiO3.

Results

Conclusion