Experiments were carried out to study the effects of several anions on the photocatalytic degradation rates of sodium dodecylbenzene sulphonate (DBS) with TiO 2 as catalyst. The anions were added as Na 2SO 4, NaNO ...Experiments were carried out to study the effects of several anions on the photocatalytic degradation rates of sodium dodecylbenzene sulphonate (DBS) with TiO 2 as catalyst. The anions were added as Na 2SO 4, NaNO 3, NaCl, NaHCO 3, NaH 2PO 4 and Na 3PO 4, and two levels of anion content, i.e. 12 mmol/L and 36 mmol/L in terms of Na +, were studied. The results revealed that: Cl -, SO 2- 4, NO - 3 and HCO - 3 retarded the rates of DBS degradation to different degrees; PO 3- 4 increased the DBS degradation rate at low concentration and decreased the rate at high concentration; H 2PO - 4 accelerated the rate of DBS degradation. The mechanism of the effects of anions on DBS degradation was concluded as the following three aspects: anions compete for the radicals; anions are absorbed on the surface of catalyst and block the active site of catalyst; anions added to the solution change the pH value and influence the formation of ·OH radicals and the adsorption of DBS on catalyst.展开更多
The study of size effect of conductivity of conducting polymer nanowires can be significant not only in the instruction of fabrication of the devices with nanodimension but also in basic research of inherence of nanom...The study of size effect of conductivity of conducting polymer nanowires can be significant not only in the instruction of fabrication of the devices with nanodimension but also in basic research of inherence of nanomaterials. PANI nanowires was fabricated in AAO templates by potentiostatic method. A new strategy of chemical modification of AAO template was introduced to prepare nanowires with smaller diameter. FTIR and contact angle measurements were used to characterize the modification. Tunneling Electron Microscopy results showed that the smaller PANI nanowires in diameter can be obtained in surfactant modified AAO templates. Conductivity of single PANI nanowire had been measured by Conductive Atomic Force Microscopy. The results displayed that the conductivity of PANI nanowire increase while the decrease of the diameter of PANI nanowires, which was called size effect of conductivity of PANI nanowires. The size effect had been attributed to order polymer chains orientation of PANI nanowire, which had been confirmed by electron diffraction diagrams.展开更多
基金TheNationalNaturalScienceFoundationofChina (No .495 710 6 2 )
文摘Experiments were carried out to study the effects of several anions on the photocatalytic degradation rates of sodium dodecylbenzene sulphonate (DBS) with TiO 2 as catalyst. The anions were added as Na 2SO 4, NaNO 3, NaCl, NaHCO 3, NaH 2PO 4 and Na 3PO 4, and two levels of anion content, i.e. 12 mmol/L and 36 mmol/L in terms of Na +, were studied. The results revealed that: Cl -, SO 2- 4, NO - 3 and HCO - 3 retarded the rates of DBS degradation to different degrees; PO 3- 4 increased the DBS degradation rate at low concentration and decreased the rate at high concentration; H 2PO - 4 accelerated the rate of DBS degradation. The mechanism of the effects of anions on DBS degradation was concluded as the following three aspects: anions compete for the radicals; anions are absorbed on the surface of catalyst and block the active site of catalyst; anions added to the solution change the pH value and influence the formation of ·OH radicals and the adsorption of DBS on catalyst.
文摘The study of size effect of conductivity of conducting polymer nanowires can be significant not only in the instruction of fabrication of the devices with nanodimension but also in basic research of inherence of nanomaterials. PANI nanowires was fabricated in AAO templates by potentiostatic method. A new strategy of chemical modification of AAO template was introduced to prepare nanowires with smaller diameter. FTIR and contact angle measurements were used to characterize the modification. Tunneling Electron Microscopy results showed that the smaller PANI nanowires in diameter can be obtained in surfactant modified AAO templates. Conductivity of single PANI nanowire had been measured by Conductive Atomic Force Microscopy. The results displayed that the conductivity of PANI nanowire increase while the decrease of the diameter of PANI nanowires, which was called size effect of conductivity of PANI nanowires. The size effect had been attributed to order polymer chains orientation of PANI nanowire, which had been confirmed by electron diffraction diagrams.
