The application of the catalysts to photocatalytic degradation of methylene blue (MB) was tested under visible light irradiation. From photocatalytic result, we found that all Zn2SnO4/CNTs composite catalysts exhibit higher MB degradation activity than add Zn2SnO4. | JOURNAL OF SCIENCE OF HNUE Mathematical and Physical Sci. 2014 Vol. 59 No. 7 pp. 144-149 This paper is available online at http PHOTOCATALYTIC COMPOSITES BASED ON Zn2 SnO4 AND CARBON NANOTUBES Nguyen Cao Khang1 Vu Quoc Trung2 Lam Thi Hang3 Nguyen Thi Thu Ha3 Nguyen Thi Lien1 Doan Thi Thuy Phuong1 Kieu Thi Bich Ngoc1 and Nguyen Van Minh1 1 Center for Nanoscience and Technology Hanoi National University of Education 2 Faculty of Chemistry Hanoi National University of Education 3 Hanoi University of Natural Resources and Environment Abstract. Zn2 SnO4 CNTs photocatalytic composite were synthesized with multi - walled carbon nanotubes MWCNTs and Zn2 SnO4 ZTO using a grinded method. The UV - V is diffuse reflectance spectra showing that the composite materials can absorb at higher wavelength and the absorption covers the entire range of the visible region. The application of the catalysts to photocatalytic degradation of methylene blue MB was tested under visible light irradiation. From photocatalytic result we found that all Zn2 SnO4 CNTs composite catalysts exhibit higher MB degradation activity than add Zn2 SnO4 . Keywords Zn2 SnO4 CNTs composite photocatalyst. 1. Introduction Zinc stannate is an n-type semiconductor with an inverse spinel structure 1 2 . Zn2 SnO4 is known for having high electron mobility high electrical conductivity and attractive optical properties all of which make it suitable for a wide range of applications such as photovoltaic devices sensors for humidity and combustible gases negative electrode material for Li-ion batteries 3-8 . In addition Zn2 SnO4 has been widely utilized as a photocatalyst because it is relatively safe inexpensive and resistant to photocorrosion. However its wide-band gap eV can capture only UV light 3 - 5 of the solar irradiance at the earth s surface compared to the 45 of visible light. Recently the authors indicated that the photocatalytic activity of some semiconductors can be improved by make a
