Photocatalytic degradation of organic pollutants is of great significance for wastewater remediation but is still hindered by the poor catalytic efficiency of the catalysts.Herein,we report a strategy to simultaneousl...Photocatalytic degradation of organic pollutants is of great significance for wastewater remediation but is still hindered by the poor catalytic efficiency of the catalysts.Herein,we report a strategy to simultaneously introduce piezocatalysis and to enhance the intrinsic photocatalysis in a single catalyst,which improved the performance for catalytic degradation of methylene blue(MB)significantly.Specifically,piezoelectric BiFeO_(3)(BFO)nanotube doped with different contents of Gd and La(Bi_(0.9)(GdxLa_(1−x))0.1FeO_(3))were produced by electrospinning.The doping led to a higher concentration of surface oxygen vacancy(OV)in Bi_(0.9)Gd_(0.07)La_(0.03)FeO_(3),which effectively increased the piezoelectric field due to the deformation of BFO,and suppressed the recombination of photon-generated electron–hole pairs.The Bi_(0.9)Gd_(0.07)La_(0.03)FeO_(3)nanotube showed excellent catalytic performance under simultaneous light irradiation and ultrasonic excitation,giving an extraordinary 95%degradation of MB within 90 min.These findings suggest that the piezoelectric effect combined with defect engineering can enhance the catalytic performance of Bi_(0.9)Gd_(0.07)La_(0.03)FeO_(3)nanotube.This could potentially be extended to other catalytic systems for high-performance pollutant treatment.展开更多
Sonophotocatalysis combines ultrasonic and light irradiations to drastically boost the chemical reaction rate and has attracted many interests for its potential applications in the environmental remediation and protec...Sonophotocatalysis combines ultrasonic and light irradiations to drastically boost the chemical reaction rate and has attracted many interests for its potential applications in the environmental remediation and protection. However, it still remains unclear whether the light irradiation could couple with the ultrasound to prompt the sonophotocatalytic process. Here, we selectively excited the TiO2 and Au to manipulate the electronic structures of Au/TiO2 and studied their influence in sonophotocatalytic water（H2 O） reduction. Surprisingly, no significant increase of the hydrogen（H2） production rate was observed under either the UV light irradiation or the visible light irradiation, suggesting that the change in electronic structures of Au/TiO2 does not prompt the generation of free radicals under sonication and the reaction is dominated by the recovery of active sites through ultrasound. Our findings established an indepth understanding of the origin of the enhanced catalytic activity in sonophotocatalysis.展开更多
基金This work was supported by the Shenzhen Government’s Plan of Science and Technology(JCYJ20190808121407676)the Natural Science Foundation of Guangdong Province(2020A1515011127)the Shenzhen University Initiative Research Program(2019005).
文摘Photocatalytic degradation of organic pollutants is of great significance for wastewater remediation but is still hindered by the poor catalytic efficiency of the catalysts.Herein,we report a strategy to simultaneously introduce piezocatalysis and to enhance the intrinsic photocatalysis in a single catalyst,which improved the performance for catalytic degradation of methylene blue(MB)significantly.Specifically,piezoelectric BiFeO_(3)(BFO)nanotube doped with different contents of Gd and La(Bi_(0.9)(GdxLa_(1−x))0.1FeO_(3))were produced by electrospinning.The doping led to a higher concentration of surface oxygen vacancy(OV)in Bi_(0.9)Gd_(0.07)La_(0.03)FeO_(3),which effectively increased the piezoelectric field due to the deformation of BFO,and suppressed the recombination of photon-generated electron–hole pairs.The Bi_(0.9)Gd_(0.07)La_(0.03)FeO_(3)nanotube showed excellent catalytic performance under simultaneous light irradiation and ultrasonic excitation,giving an extraordinary 95%degradation of MB within 90 min.These findings suggest that the piezoelectric effect combined with defect engineering can enhance the catalytic performance of Bi_(0.9)Gd_(0.07)La_(0.03)FeO_(3)nanotube.This could potentially be extended to other catalytic systems for high-performance pollutant treatment.
基金supported by the National Science Foundation 9(NSF, No. DMR-1352328)supported by the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, under Contract No. DE-SC0012704
文摘Sonophotocatalysis combines ultrasonic and light irradiations to drastically boost the chemical reaction rate and has attracted many interests for its potential applications in the environmental remediation and protection. However, it still remains unclear whether the light irradiation could couple with the ultrasound to prompt the sonophotocatalytic process. Here, we selectively excited the TiO2 and Au to manipulate the electronic structures of Au/TiO2 and studied their influence in sonophotocatalytic water（H2 O） reduction. Surprisingly, no significant increase of the hydrogen（H2） production rate was observed under either the UV light irradiation or the visible light irradiation, suggesting that the change in electronic structures of Au/TiO2 does not prompt the generation of free radicals under sonication and the reaction is dominated by the recovery of active sites through ultrasound. Our findings established an indepth understanding of the origin of the enhanced catalytic activity in sonophotocatalysis.
