Self Assembled Monolayers(SAMs) of a series of mercapto contained azobenzene derivatives with the structure of C n H 2 n +1 AzoO(CH 2) m SH (where n =4,6,8,10,12; with m =3,5 respectively) were prepared and characteri...Self Assembled Monolayers(SAMs) of a series of mercapto contained azobenzene derivatives with the structure of C n H 2 n +1 AzoO(CH 2) m SH (where n =4,6,8,10,12; with m =3,5 respectively) were prepared and characterized.Wettability measurement of water on the SAMs demonstrates that molecular packing density in the monolayers increases while the alkyl chain in the molecules is lengthened. Both the n and m values have similar contribution to the wetting property of SAMs. The RA IR spectra reveal that the alkyl chains in the SAMs tilt away dramatically from the surface normal direction with the increase in their length. However, the orientation of azobenzene moiety is found to be influenced slightly by the alkyl chain length, which is due to the tenderness of the molecule.展开更多
The formation kinetics of the self-assembled monolayer (SAM) of an azobenzenealkanethiol,denoted as AzoC2SH on surface was studied using electrochemical techniques,and the monolayers prepared at different assembly tim...The formation kinetics of the self-assembled monolayer (SAM) of an azobenzenealkanethiol,denoted as AzoC2SH on surface was studied using electrochemical techniques,and the monolayers prepared at different assembly times and concentration were also investigated.A two-step adsorption kinetics has been confirmed:the fast adsorption process and the following long-term reorganization.The equilibrium constant(K)for the adsorptioon and the interaction factor between adsorbate-adsorbate molecules () were evaluated based on the Frumkin isotherm and determined to be (3. 17±0. 13)× 106 mol.L(-1) and -0.34±0.04, respectively The Gibbs free energy (G)of SAM was determined to be -(37. 07±0. 13)kJ.mol(-1)展开更多
A novel quinoline derivative 6-(10-thiol-decaoxy ) quinoine (abbreviated as QC10SH )was synthesized and its seif-assembled monoayers (SAMs) were prepared on gold for the first time. Wettability measurement on QC10SH S...A novel quinoline derivative 6-(10-thiol-decaoxy ) quinoine (abbreviated as QC10SH )was synthesized and its seif-assembled monoayers (SAMs) were prepared on gold for the first time. Wettability measurement on QC10SH SAM reveals a hydrophilic surface. RA-IR researches suggests that the SAM has formed highly-organized and closely-packed structure. A method is developed for quanitatively evaluating the molecular orientation in monoayer. By this method the result that the twisting and tilting angles of QC10SH moecule in SAM are 50±4° and 24±3°respectively has been obtained.展开更多
文摘Self Assembled Monolayers(SAMs) of a series of mercapto contained azobenzene derivatives with the structure of C n H 2 n +1 AzoO(CH 2) m SH (where n =4,6,8,10,12; with m =3,5 respectively) were prepared and characterized.Wettability measurement of water on the SAMs demonstrates that molecular packing density in the monolayers increases while the alkyl chain in the molecules is lengthened. Both the n and m values have similar contribution to the wetting property of SAMs. The RA IR spectra reveal that the alkyl chains in the SAMs tilt away dramatically from the surface normal direction with the increase in their length. However, the orientation of azobenzene moiety is found to be influenced slightly by the alkyl chain length, which is due to the tenderness of the molecule.
文摘The formation kinetics of the self-assembled monolayer (SAM) of an azobenzenealkanethiol,denoted as AzoC2SH on surface was studied using electrochemical techniques,and the monolayers prepared at different assembly times and concentration were also investigated.A two-step adsorption kinetics has been confirmed:the fast adsorption process and the following long-term reorganization.The equilibrium constant(K)for the adsorptioon and the interaction factor between adsorbate-adsorbate molecules () were evaluated based on the Frumkin isotherm and determined to be (3. 17±0. 13)× 106 mol.L(-1) and -0.34±0.04, respectively The Gibbs free energy (G)of SAM was determined to be -(37. 07±0. 13)kJ.mol(-1)
文摘A novel quinoline derivative 6-(10-thiol-decaoxy ) quinoine (abbreviated as QC10SH )was synthesized and its seif-assembled monoayers (SAMs) were prepared on gold for the first time. Wettability measurement on QC10SH SAM reveals a hydrophilic surface. RA-IR researches suggests that the SAM has formed highly-organized and closely-packed structure. A method is developed for quanitatively evaluating the molecular orientation in monoayer. By this method the result that the twisting and tilting angles of QC10SH moecule in SAM are 50±4° and 24±3°respectively has been obtained.
