In this work, a series of Cu2O-Ag/ZnO, Cu2O/ZnO and Ag/ZnO nanocomposites with various compositions were prepared via a hydrothermal method followed by chemical modification, and their antibacterial performance was in...In this work, a series of Cu2O-Ag/ZnO, Cu2O/ZnO and Ag/ZnO nanocomposites with various compositions were prepared via a hydrothermal method followed by chemical modification, and their antibacterial performance was investigated in detail. X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy results confirmed that 31 nm Cu20 and 30 nm Ag nanoparticles are well-dispersed on 202 nm ZnO grains to form a Cu2O/ZnO and Ag/ZnO heterojunction, respectively. The bi-heterojuction structure in the Cu20-Ag/ZnO provided a synergistic effect on antibacterial activity, and the(Cu2O)0.04Ag0.06ZnO0.9nanocomposites showed the highest antimicrobial activity of all samples with minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli and Staphylococcus aureus as low to 31.25 μg/mL, 250μg/mL, 125μg/mL and 500μg/mL, respectively. This is the first report of the antibacterial activities of Cu2O and Ag co-modified ZnO nanocomposites.展开更多
A new form of Cu2O, disk-like structure with 60 nm in thickness and 2 μm in diameter,has been successfully synthesized in bulk quantities by polyol process in the presence of PVP K-30.
An efficient process for the conversion of dimethyl oxalateinto ethylene glycol with high selectivity and high yield over CuO was investigated. In situ formed Cu as a true catalytically active species showed a good ca...An efficient process for the conversion of dimethyl oxalateinto ethylene glycol with high selectivity and high yield over CuO was investigated. In situ formed Cu as a true catalytically active species showed a good catalytic performance for DMO conversion to produce EG in 95% yield.展开更多
Reaction between Cu_2S and Cu_2O was investigated at 1150 to 1250℃.The reaction rate in- creases with the increase of surface area of Cu_2O grains and depends unobviously on temper- ature.At the suggestion of control...Reaction between Cu_2S and Cu_2O was investigated at 1150 to 1250℃.The reaction rate in- creases with the increase of surface area of Cu_2O grains and depends unobviously on temper- ature.At the suggestion of controlling step of reaction rate being oxygen diffusion through the liquid layer along reaction boundaries,two final kinetical equations would be made as follows: x=6.69×10^(-2)At for 0<α<0.74 and ln(l-α)=-A(9.83×10^(-2)t+1.76)for 0.74<α<1,where α is SO_2 evolved in time t and A is surface area of Cu_2O particles.展开更多
基金supported in part by the National Natural Science Foundation of China(Grant Nos.51677120 and 51207093)the Shenzhen Government Fund(Grant Nos.JCYJ20160422102919963)the Shenzhen Key Laboratory of Special Functional Materials(Grant Nos.T201502)
文摘In this work, a series of Cu2O-Ag/ZnO, Cu2O/ZnO and Ag/ZnO nanocomposites with various compositions were prepared via a hydrothermal method followed by chemical modification, and their antibacterial performance was investigated in detail. X-ray powder diffraction, scanning electron microscopy and transmission electron microscopy results confirmed that 31 nm Cu20 and 30 nm Ag nanoparticles are well-dispersed on 202 nm ZnO grains to form a Cu2O/ZnO and Ag/ZnO heterojunction, respectively. The bi-heterojuction structure in the Cu20-Ag/ZnO provided a synergistic effect on antibacterial activity, and the(Cu2O)0.04Ag0.06ZnO0.9nanocomposites showed the highest antimicrobial activity of all samples with minimum inhibitory concentration and minimum bactericidal concentration against Escherichia coli and Staphylococcus aureus as low to 31.25 μg/mL, 250μg/mL, 125μg/mL and 500μg/mL, respectively. This is the first report of the antibacterial activities of Cu2O and Ag co-modified ZnO nanocomposites.
基金This work was supported by the National Natural Science Foundation of ChinaNatural Science Foundation of Qinghai Province.
文摘A new form of Cu2O, disk-like structure with 60 nm in thickness and 2 μm in diameter,has been successfully synthesized in bulk quantities by polyol process in the presence of PVP K-30.
基金financial support from the State Key Program of National Natural Science Foundation of China(No.21436007)Key Basic Research Projects of Science and Technology Commission of Shanghai(14JC1403100)+2 种基金the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning(ZXDF160002)the Projectsponsored by SRF for ROCS,SEM(BG1600002)State Key Laboratory of Fine Chemicals(KF1411)
文摘An efficient process for the conversion of dimethyl oxalateinto ethylene glycol with high selectivity and high yield over CuO was investigated. In situ formed Cu as a true catalytically active species showed a good catalytic performance for DMO conversion to produce EG in 95% yield.
文摘Reaction between Cu_2S and Cu_2O was investigated at 1150 to 1250℃.The reaction rate in- creases with the increase of surface area of Cu_2O grains and depends unobviously on temper- ature.At the suggestion of controlling step of reaction rate being oxygen diffusion through the liquid layer along reaction boundaries,two final kinetical equations would be made as follows: x=6.69×10^(-2)At for 0<α<0.74 and ln(l-α)=-A(9.83×10^(-2)t+1.76)for 0.74<α<1,where α is SO_2 evolved in time t and A is surface area of Cu_2O particles.
