A Keggin-type polyoxomolybdate[H2biim]{Ni(biim)3(SiMO12O40)}[biim =1H,1'H-[2,2']biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-ind...A Keggin-type polyoxomolybdate[H2biim]{Ni(biim)3(SiMO12O40)}[biim =1H,1'H-[2,2']biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-induced and magnetism-induced 2D infrared correlation spectroscopy(2D-IR COS)and UV-vis DRS in order to explore the relationship between structure and properties.Temperatureinduced 2D-IR COS spectroscopy indicates that the terminal Mo-Oμ/υbonds are more sensitive than the bridging Mo=Ot,bands to temperature variation,which is in agreement with the conclusion of temperature-dependent IR.Magnetism-dependent 2D-IR COS spectroscopy reveals the stretching vibration of the Mo=Ot,occurs prior to the stretching vibration of the Mo-Oμ/υ,which is due to the coordination environment and the valence of the Si atom.The stability of compound 1 is investigated via TG and temperature-dependent IR.In RhB degradation,compound 1 shows good photocatalytic abilities.展开更多
C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface...C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface area(345 m^2/g) and large mesopore size(ca. 4.2 nm), capable of offering more accessible active sites as well as faster mass transfer for catalysis. Besides, the doping of C(2.21%, molar fraction) at the O sites in Nb2O5 lattice greatly enhanced visible-light response by lowering the band gap, thereby making the material a photocatalyst under visible-light irradiation. Typically, the C-doped Nb2O5 exhibited a high H2 evolution rate of ca. 39.10·μmol·g^-1·h^-1 and also degraded RhB dye completely after 30 min of visible light exposure, which turned out to be much better than Degussa P25 and pure Nb2O5 catalysts.展开更多
Human health is deteriorating due to the effluent containing heavy metal ions and organic dyes.Hence,photoreduction of Cr(Ⅵ)to Cr(Ⅲ)and degradation of rhodamine B(RhB)using a novel photocatalyst is particularly impo...Human health is deteriorating due to the effluent containing heavy metal ions and organic dyes.Hence,photoreduction of Cr(Ⅵ)to Cr(Ⅲ)and degradation of rhodamine B(RhB)using a novel photocatalyst is particularly important.In this work,h-BN/NiS_(2)/NiS composites were prepared via a simple solvothermal method and a double Z-scheme heterojunction was constructed for efficiently removing RhB and Cr(Ⅵ).The 7 wt-%h-BN/NiS_(2)/NiS composites were characterized via a larger specific surface area(15.12 m^(2)·g^(−1)),stronger light absorption capacity,excellent chemical stability,and high yield of electrons and holes.The experimental result indicated that the photoreduction efficiency of the 7 wt-%h-BN/NiS_(2)/NiS photocatalyst achieved 98.5%for Cr(Ⅵ)after 120 min,which was about 3 times higher than that of NiS_(2)/NiS(34%).However,the removal rate of RhB by the 7 wt-%h-BN/NiS_(2)/NiS photocatalyst reached 80%.This is due to the double Z-scheme heterojunction formed between NiS_(2)/NiS and h-BN,which improved the charge separation efficiency and transmission efficiency.Besides,the influence of diverse photogenerated electron and hole scavengers upon the photoreduction of Cr(Ⅵ)was studied,the results indicated that graphene-like h-BN promoted transportation of photoinduced charges on the surface of the h-BN/NiS_(2)/NiS photocatalyst via the interfacial effects.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51373003)Beijing Natural Science Foundation(No.2122059)Open Fund of State Key Laboratory of Structural Chemistry(No.20130015) and Science
文摘A Keggin-type polyoxomolybdate[H2biim]{Ni(biim)3(SiMO12O40)}[biim =1H,1'H-[2,2']biimidazolyl]has been synthesized under hydrothermal condition and characterized by XRD,temperature-dependent IR,TG,temperature-induced and magnetism-induced 2D infrared correlation spectroscopy(2D-IR COS)and UV-vis DRS in order to explore the relationship between structure and properties.Temperatureinduced 2D-IR COS spectroscopy indicates that the terminal Mo-Oμ/υbonds are more sensitive than the bridging Mo=Ot,bands to temperature variation,which is in agreement with the conclusion of temperature-dependent IR.Magnetism-dependent 2D-IR COS spectroscopy reveals the stretching vibration of the Mo=Ot,occurs prior to the stretching vibration of the Mo-Oμ/υ,which is due to the coordination environment and the valence of the Si atom.The stability of compound 1 is investigated via TG and temperature-dependent IR.In RhB degradation,compound 1 shows good photocatalytic abilities.
基金Supported by the National Natural Science Foundation of China(No.21390394) and the National Basic Research Program of China(Nos. 2012CB821700, 2011CB808703).
文摘C-doped Nb2O5 with abundant mesopores has been successfully synthesized through a facile solvothermal synthetic strategy followed by calcination treatment. The resulting C-doped Nb2O5 displayed the highest BET surface area(345 m^2/g) and large mesopore size(ca. 4.2 nm), capable of offering more accessible active sites as well as faster mass transfer for catalysis. Besides, the doping of C(2.21%, molar fraction) at the O sites in Nb2O5 lattice greatly enhanced visible-light response by lowering the band gap, thereby making the material a photocatalyst under visible-light irradiation. Typically, the C-doped Nb2O5 exhibited a high H2 evolution rate of ca. 39.10·μmol·g^-1·h^-1 and also degraded RhB dye completely after 30 min of visible light exposure, which turned out to be much better than Degussa P25 and pure Nb2O5 catalysts.
基金supported by Program for Science&Technology Innovative Research Team in the University of Henan Province(Grant No.21IRTSTHN006)Program for Science&Technology Innovation Talents in Universities of Henan Province(Grant No.19HAS-TIT042)+1 种基金Key scientific and technological project in Henan Province(Grant No.212102210179)Program for Innovative Research Team of Henan Polytechnic University(Grant Nos.T2018-2,T2019-1).
文摘Human health is deteriorating due to the effluent containing heavy metal ions and organic dyes.Hence,photoreduction of Cr(Ⅵ)to Cr(Ⅲ)and degradation of rhodamine B(RhB)using a novel photocatalyst is particularly important.In this work,h-BN/NiS_(2)/NiS composites were prepared via a simple solvothermal method and a double Z-scheme heterojunction was constructed for efficiently removing RhB and Cr(Ⅵ).The 7 wt-%h-BN/NiS_(2)/NiS composites were characterized via a larger specific surface area(15.12 m^(2)·g^(−1)),stronger light absorption capacity,excellent chemical stability,and high yield of electrons and holes.The experimental result indicated that the photoreduction efficiency of the 7 wt-%h-BN/NiS_(2)/NiS photocatalyst achieved 98.5%for Cr(Ⅵ)after 120 min,which was about 3 times higher than that of NiS_(2)/NiS(34%).However,the removal rate of RhB by the 7 wt-%h-BN/NiS_(2)/NiS photocatalyst reached 80%.This is due to the double Z-scheme heterojunction formed between NiS_(2)/NiS and h-BN,which improved the charge separation efficiency and transmission efficiency.Besides,the influence of diverse photogenerated electron and hole scavengers upon the photoreduction of Cr(Ⅵ)was studied,the results indicated that graphene-like h-BN promoted transportation of photoinduced charges on the surface of the h-BN/NiS_(2)/NiS photocatalyst via the interfacial effects.