Synthesis of amorphous CoSn(OH)6 nanocubes for photocatalytic reduction of 4-nitrophenol

Catalytic reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) is an important method for treating toxic nitroaromatic pollutant. In this work, amorphous CoSn(OH)(6) nanocubes were synthesized by coprecipitation and calcination methods for 4-NP photocatalytic reduction. The crystal structure, morphology and optical property of the samples were characterized by XRD, SEM, TEM, XPS, and UV-vis DRS. The amorphous CoSn(OH)(6) nanocubes showed excellent photocatalytic performance in 4-NP reduction. The effects of catalyst dosage, 4-NP concentration, and sodium borohydride concentration on the conversion rate of 4-NP were investigated. The results showed that the conversion rate of 4-NP could reach 98.38% in 15 min at room temperature under visible light irradiation. After five cycles of experiments, the conversion rate of 4-NP remained above 90%, indicating the good catalytic stability of the amorphous CoSn(OH)(6) nanocubes. Finally, the mechanisms of photocatalytic reduction on amorphous CoSn(OH)(6) nanocubes are also discussed. The successful preparation of amorphous CoSn(OH)(6) nanocubes may enable the widespread use of amorphous polymetallic oxides for the removal of nitrophenols from wastewater in the future. [GRAPHICS]