The hydrophobic ionic liquids/water two-phase system was developed to prepare CuO nano particles.The catalytic activity of the synthesized CuO was investigated by photodegradation of 4-nitrophenol(4-NP)in the presence...The hydrophobic ionic liquids/water two-phase system was developed to prepare CuO nano particles.The catalytic activity of the synthesized CuO was investigated by photodegradation of 4-nitrophenol(4-NP)in the presence of H_(2)O_(2) under visible light irradiation.The optical properties of the synthesized CuO were characterized by ultraviolet–visible(UV–Vis)diffuse reflectance spectroscopy(DRS).Experimental results indicated that the band gap energy(Eg),conduction band edge potential(ECB)and valence band edge potential(EVB)of the synthesized CuO were 1.37 e V,0.625 e V and 1.995 e V,respectively.A degradation efficiency of 4-NP(4.8 mmol L^(-1))as high as 95.3% could be achieved under the conditions of p H 6.0,0.48 g L^(-1)of CuO dosage,1.4% of H_(2)O_(2) dosage and 90 min of degradation time.The synthesized CuO exhibited poor catalytic activity under alkaline conditions due to the disassociation of 4-NP,which elevated the repulsion between CuO and the 4-NP anions.The synthesized CuO nano particles exhibited higher catalytic activity compared with the catalysts reported in literature.Furthermore,the synthesized CuO nano particles could be reused at least six times without decreasing their catalytic activity.Compared with the traditional hydrothermal method,mild operating conditions and time saving are the advantages of the developed method for the preparation of CuO.展开更多
The 96 h acute toxic effects of nano-CuO (N-CuO), micro-CuO (M-CuO) and 2+ on Chlorella sp. were investigated in this paper. The results showed that toxicities decreased in an order of Cu2+>N-CuO>M-CuO. The 96 h...The 96 h acute toxic effects of nano-CuO (N-CuO), micro-CuO (M-CuO) and 2+ on Chlorella sp. were investigated in this paper. The results showed that toxicities decreased in an order of Cu2+>N-CuO>M-CuO. The 96 h EC50 of Cu2+ on Chlorella sp. was 1.06 mg /L, and of N-CuO it was 74.61 mg /L, while no pronounced toxicity was observed when the concentration of M-CuO was lower than 160 mg/L. Further experiments were carried out in order to study the toxicity mechanism of nano-CuO on Chlorella sp.. The results of Cu2+ release from N-CuO showed less than 0.2 mg/L Cu2+ were released, so the release of Cu2+ was not responsible for the toxicity. Further experiments showed N-CuO inhibited formation of Chlorophyll A. Content of Chlorophyll A in the control group was 4.75 mg/108 cells, while it declined to 2.89 mg/108 cells for 160 mg/L N-CuO after 96 h, which indicated that N-CuO could inhibit photosynthesis of Chlorella sp.. Moreover, N-CuO condensed with algal cells. It affected the activity of SOD and POD, indicating that N-CuO could cause oxidant stress to Chlorella sp.. These may be the toxicity mechanism.展开更多
Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 C.Fe3O4 NPs/GOCuO NPs is found to be a...Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 C.Fe3O4 NPs/GOCuO NPs is found to be an efficient catalyst for the A^3-coupling of aldehydes,amines,and alkynes through C-H activation.Both aromatic and aliphatic aldehydes and alkynes are combined with secondary amines to provide a wide range of propargylamines in moderate to excellent yields.展开更多
Nano-scale copper oxide with various morphologies is synthesized via the thermal oxide method and growth in a 5 wt% NaCl solution of spray fog environment. The nano-scale copper oxide is grown on copper metal sheets v...Nano-scale copper oxide with various morphologies is synthesized via the thermal oxide method and growth in a 5 wt% NaCl solution of spray fog environment. The nano-scale copper oxide is grown on copper metal sheets via the thermal oxide method at 650℃ for 60 minutes. Nano-scale copper oxide grains and nanowires are induced on copper metal sheets then placed in 5 wt% NaCl solution of salt spray fog environment. Significant changes in particle size and mor-phology are observed with increasing salt spray fog treatement time. The morphology of nano-scale copper oxide varies from nanograins to nanowires, Ctahedron, and icositetrahedron. The morphologies and structures of the obtained nano-scale copper oxide are investigated by scanning electron microscopy and energy-dispersive spectroscopy. Possible growth mechanisms are discussed.展开更多
Nano-CuO was prepared by heating nano-Cu2(OH)2CO3 precursors in different calcination temperatures. The precursor was synthesized from water-alcohol mixed solution of Cu(Ac)2 using mixed solution of NaOH and Na2CO3 as...Nano-CuO was prepared by heating nano-Cu2(OH)2CO3 precursors in different calcination temperatures. The precursor was synthesized from water-alcohol mixed solution of Cu(Ac)2 using mixed solution of NaOH and Na2CO3 as precipitants. XRD, FT-IR, TEM, TG-DTA and surface area measurement techniques were used to investigate the properties of the CuO powder. The results show that the spherical, well dispersed nano-CuO powder with the average size of 15 nm and higher catalytic activity for H2O2 decomposition was obtained at 300 ℃. With the increasing of calcination temperature, crystal of CuO grows up, agglomeration of the powder becomes heavier and catalytic activity decreases. FT-IR patterns revealed that the vibration fine structure of Cu-O bond in nano-CuO powder disappears and main absorption is red-shifted with the average size of nano-CuO reducing.展开更多
基金supported by the Foundation of Henan Province(Nos.202102310614,182102310300,18A150028)the Foundation of Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Soochow University(No.KJS2016)the Foundation of Henan Polytechnic University(No.NSFRF200313)。
文摘The hydrophobic ionic liquids/water two-phase system was developed to prepare CuO nano particles.The catalytic activity of the synthesized CuO was investigated by photodegradation of 4-nitrophenol(4-NP)in the presence of H_(2)O_(2) under visible light irradiation.The optical properties of the synthesized CuO were characterized by ultraviolet–visible(UV–Vis)diffuse reflectance spectroscopy(DRS).Experimental results indicated that the band gap energy(Eg),conduction band edge potential(ECB)and valence band edge potential(EVB)of the synthesized CuO were 1.37 e V,0.625 e V and 1.995 e V,respectively.A degradation efficiency of 4-NP(4.8 mmol L^(-1))as high as 95.3% could be achieved under the conditions of p H 6.0,0.48 g L^(-1)of CuO dosage,1.4% of H_(2)O_(2) dosage and 90 min of degradation time.The synthesized CuO exhibited poor catalytic activity under alkaline conditions due to the disassociation of 4-NP,which elevated the repulsion between CuO and the 4-NP anions.The synthesized CuO nano particles exhibited higher catalytic activity compared with the catalysts reported in literature.Furthermore,the synthesized CuO nano particles could be reused at least six times without decreasing their catalytic activity.Compared with the traditional hydrothermal method,mild operating conditions and time saving are the advantages of the developed method for the preparation of CuO.
文摘The 96 h acute toxic effects of nano-CuO (N-CuO), micro-CuO (M-CuO) and 2+ on Chlorella sp. were investigated in this paper. The results showed that toxicities decreased in an order of Cu2+>N-CuO>M-CuO. The 96 h EC50 of Cu2+ on Chlorella sp. was 1.06 mg /L, and of N-CuO it was 74.61 mg /L, while no pronounced toxicity was observed when the concentration of M-CuO was lower than 160 mg/L. Further experiments were carried out in order to study the toxicity mechanism of nano-CuO on Chlorella sp.. The results of Cu2+ release from N-CuO showed less than 0.2 mg/L Cu2+ were released, so the release of Cu2+ was not responsible for the toxicity. Further experiments showed N-CuO inhibited formation of Chlorophyll A. Content of Chlorophyll A in the control group was 4.75 mg/108 cells, while it declined to 2.89 mg/108 cells for 160 mg/L N-CuO after 96 h, which indicated that N-CuO could inhibit photosynthesis of Chlorella sp.. Moreover, N-CuO condensed with algal cells. It affected the activity of SOD and POD, indicating that N-CuO could cause oxidant stress to Chlorella sp.. These may be the toxicity mechanism.
文摘Magnetically separable CuO nanoparticles supported on graphene oxide（Fe3O4 NPs/GO-CuO NPs） is synthesized and characterized for the preparation of propargylamines in EtOH,at 90 C.Fe3O4 NPs/GOCuO NPs is found to be an efficient catalyst for the A^3-coupling of aldehydes,amines,and alkynes through C-H activation.Both aromatic and aliphatic aldehydes and alkynes are combined with secondary amines to provide a wide range of propargylamines in moderate to excellent yields.
文摘Nano-scale copper oxide with various morphologies is synthesized via the thermal oxide method and growth in a 5 wt% NaCl solution of spray fog environment. The nano-scale copper oxide is grown on copper metal sheets via the thermal oxide method at 650℃ for 60 minutes. Nano-scale copper oxide grains and nanowires are induced on copper metal sheets then placed in 5 wt% NaCl solution of salt spray fog environment. Significant changes in particle size and mor-phology are observed with increasing salt spray fog treatement time. The morphology of nano-scale copper oxide varies from nanograins to nanowires, Ctahedron, and icositetrahedron. The morphologies and structures of the obtained nano-scale copper oxide are investigated by scanning electron microscopy and energy-dispersive spectroscopy. Possible growth mechanisms are discussed.
文摘Nano-CuO was prepared by heating nano-Cu2(OH)2CO3 precursors in different calcination temperatures. The precursor was synthesized from water-alcohol mixed solution of Cu(Ac)2 using mixed solution of NaOH and Na2CO3 as precipitants. XRD, FT-IR, TEM, TG-DTA and surface area measurement techniques were used to investigate the properties of the CuO powder. The results show that the spherical, well dispersed nano-CuO powder with the average size of 15 nm and higher catalytic activity for H2O2 decomposition was obtained at 300 ℃. With the increasing of calcination temperature, crystal of CuO grows up, agglomeration of the powder becomes heavier and catalytic activity decreases. FT-IR patterns revealed that the vibration fine structure of Cu-O bond in nano-CuO powder disappears and main absorption is red-shifted with the average size of nano-CuO reducing.
