We investigate the dielectric and ferroelectric properties of Sr1-xBixTi1-xFex03 solid solutions （x =0, 0.05, 0.1, 0.15 and 0.2） together with their structures. Through the analysis of Rietveld refinement of powder ...We investigate the dielectric and ferroelectric properties of Sr1-xBixTi1-xFex03 solid solutions （x =0, 0.05, 0.1, 0.15 and 0.2） together with their structures. Through the analysis of Rietveld refinement of powder x-ray diffraction, a cubic structure in space group Pm3m is determined for all the compositions. An obvious dielectric relaxation peak differing from SrTiO3 is observed in the present ceramics. The peak temperature Tm increases with increasing x, and it approaches room temperature at x =0.2. The Vogel Fulcher law and Curie Weiss law fittings further confirm the relaxor ferroelectricity in the present ceramics.展开更多
Heterostructure is an effective strategy to facilitate the charge carrier separation and promote the photocatalytic performance.In this paper,uniform SrTiO3 nanocubes were in-situ grown on TiO2 nanowires to construct ...Heterostructure is an effective strategy to facilitate the charge carrier separation and promote the photocatalytic performance.In this paper,uniform SrTiO3 nanocubes were in-situ grown on TiO2 nanowires to construct heterojunctions.The composites were prepared by a facile alkaline hydrothermal method and an in-situ deposition method.The obtained SrTiO3/TiO2 exhibits much better photocatalytic activity than those of pure TiO2 nanowires and commercial TiO2(P25)evaluated by photocatalytic water splitting and decomposition of Rhodamine B(RB).The hydrogen generation rate of SrTiO3/TiO2 nanowires could reach 111.26 mmol·g^−1·h^−1 at room temperature,much better than those of pure TiO2 nanowires(44.18 mmol·g^−1·h^−1)and P25(35.77 mmol·g^−1·h^−1).The RB decomposition rate of SrTiO3/TiO2 is 7.2 times of P25 and 2.4 times of pure TiO2 nanowires.The photocatalytic activity increases initially and then decreases with the rising content of SrTiO3,suggesting an optimum SrTiO3/TiO2 ratio that can further enhance the catalytic activity.The improved photocatalytic activity of SrTiO3/TiO2 is principally attributed to the enhanced charge separation deriving from the SrTiO3/TiO2 heterojunction.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 51332006,11274270,and 51272233
文摘We investigate the dielectric and ferroelectric properties of Sr1-xBixTi1-xFex03 solid solutions （x =0, 0.05, 0.1, 0.15 and 0.2） together with their structures. Through the analysis of Rietveld refinement of powder x-ray diffraction, a cubic structure in space group Pm3m is determined for all the compositions. An obvious dielectric relaxation peak differing from SrTiO3 is observed in the present ceramics. The peak temperature Tm increases with increasing x, and it approaches room temperature at x =0.2. The Vogel Fulcher law and Curie Weiss law fittings further confirm the relaxor ferroelectricity in the present ceramics.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.51572145).
文摘Heterostructure is an effective strategy to facilitate the charge carrier separation and promote the photocatalytic performance.In this paper,uniform SrTiO3 nanocubes were in-situ grown on TiO2 nanowires to construct heterojunctions.The composites were prepared by a facile alkaline hydrothermal method and an in-situ deposition method.The obtained SrTiO3/TiO2 exhibits much better photocatalytic activity than those of pure TiO2 nanowires and commercial TiO2(P25)evaluated by photocatalytic water splitting and decomposition of Rhodamine B(RB).The hydrogen generation rate of SrTiO3/TiO2 nanowires could reach 111.26 mmol·g^−1·h^−1 at room temperature,much better than those of pure TiO2 nanowires(44.18 mmol·g^−1·h^−1)and P25(35.77 mmol·g^−1·h^−1).The RB decomposition rate of SrTiO3/TiO2 is 7.2 times of P25 and 2.4 times of pure TiO2 nanowires.The photocatalytic activity increases initially and then decreases with the rising content of SrTiO3,suggesting an optimum SrTiO3/TiO2 ratio that can further enhance the catalytic activity.The improved photocatalytic activity of SrTiO3/TiO2 is principally attributed to the enhanced charge separation deriving from the SrTiO3/TiO2 heterojunction.
