Nitric acid-assisted one-step solvothermal synthesis of visible-light-active N-doped ThO2 for use as a potential photocatalyst in the reduction of Cr(VI)

• Published in: Catalysis communications 2017-08, Vol.99, p.66-70
• Main Authors: Wei, Hongtao, Wen, Yaoting, Zhang, Yongcai
• Format: Article
• Language: English
• Subjects: Cr(VI) reduction; Homogenous catalysis; N-doped ThO2; Visible-light photocatalyst
• ISSN: 1566-7367; 1873-3905
• DOI: 10.1016/j.catcom.2017.05.030

Nanostructure N-doped ThO2 (which was named as ThO2-HNO3) was synthesized by solvothermal treatment of Th(NO3)4·4H2O in the mixed solution of absolute ethanol (92.5vol%) and nitric acid (7.5vol%) at 180°C for 20h. ThO2-HNO3 exhibited significant visible-light absorption and high photocatalytic activity in the reduction of aqueous Cr(VI) under visible-light (wavelength>420nm) irradiation. By contrast, the commercial ThO2 and the ThO2 synthesized when ammonia replaced nitric acid exhibited only negligible visible-light photocatalytic activity. Thus, ThO2-HNO3 is a new alternative visible-light photocatalyst for treating Cr(VI)-polluted wastewaters. [Display omitted] •N-doped ThO2 was synthesized by a nitric acid-assisted one-step solvothermal method.•N-doped ThO2 exhibited obvious absorption of visible-light.•N-doped ThO2 had high visible-light photocatalytic activity in Cr(VI) reduction.•Highly toxic Cr(VI) was reduced to much less toxic Cr(III).•The ThO2 synthesized using ammonia had little visible-light photocatalytic activity.