Electrochemical Scanning TUnneling Microscopy (ECSTM) has been extended to characterizc polycrystalline silver electrode surfaces in iodide solution. Potential-dependcnt ordered and disordered structures of the silver...Electrochemical Scanning TUnneling Microscopy (ECSTM) has been extended to characterizc polycrystalline silver electrode surfaces in iodide solution. Potential-dependcnt ordered and disordered structures of the silver electrode as well as the iodine adsorption layer have been obscrved to coexist on polycrystalline silver electrode surfaces, for the first time. A very special column arrangement of the iodine adsorption layer, similar to the so called "ndssing row" type of structure has been obseryed. Some columns of the iodine adsorption layer roll over from one place to another along with the time and changing potential. A proposed model has been given to better describe the structure. The highly corrugated and loose surface structure of the polycrystalline surface are responsible for this special phenomenon.展开更多
Surface enhanced raman spectrosscopy (SERS)has been used to studey the electrochemical coadsorption of TU at silver electrodes in solutions containing nitric acid ,sulphuric acid and perchloric acid respectively or an...Surface enhanced raman spectrosscopy (SERS)has been used to studey the electrochemical coadsorption of TU at silver electrodes in solutions containing nitric acid ,sulphuric acid and perchloric acid respectively or any two of them.It was found that these different anions can be induce-coadsorbed simultaneously on the silver surface through the protonated amino group of TU in the mixed acids ysstem.The coadsorption ability of the anions are in the order of So>NO?CLO at the potentials of at the potentials of The stability of TU on the surface of Agelectrode depends not only on the electrode potential but also on the nature of electrolyte anions coadsopbed.展开更多
Mass-selected C60 beam produced by laser ablation was accelerated and bombarded the (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold single crystal. The samples were characterized by STM....Mass-selected C60 beam produced by laser ablation was accelerated and bombarded the (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold single crystal. The samples were characterized by STM. The STM images showed that, the deposited species collapsed and formed planar structure on the solid surface, but the collapsed species were not dissociated and well oriented on the surface. Both positive and negative C60 ions were observed in the desorption mass spectra, confirming that the species collapsed on the solid surface are still the C60 clusters.展开更多
Two kinds of DNA-modified electrodes were prepared by covalent and adsorptive immobilization of DNA onto self-assembled monolayers of 2, 2’-dithiodiethanol on gold electrodes and characterized by cyclic voltammetry, ...Two kinds of DNA-modified electrodes were prepared by covalent and adsorptive immobilization of DNA onto self-assembled monolayers of 2, 2’-dithiodiethanol on gold electrodes and characterized by cyclic voltammetry, Xray photoelectron spectroscopy and scanning tunneling microscopy. The results suggest that the methods are satisfactory for the immobilization of DNA on electrodes.展开更多
文摘Electrochemical Scanning TUnneling Microscopy (ECSTM) has been extended to characterizc polycrystalline silver electrode surfaces in iodide solution. Potential-dependcnt ordered and disordered structures of the silver electrode as well as the iodine adsorption layer have been obscrved to coexist on polycrystalline silver electrode surfaces, for the first time. A very special column arrangement of the iodine adsorption layer, similar to the so called "ndssing row" type of structure has been obseryed. Some columns of the iodine adsorption layer roll over from one place to another along with the time and changing potential. A proposed model has been given to better describe the structure. The highly corrugated and loose surface structure of the polycrystalline surface are responsible for this special phenomenon.
文摘Surface enhanced raman spectrosscopy (SERS)has been used to studey the electrochemical coadsorption of TU at silver electrodes in solutions containing nitric acid ,sulphuric acid and perchloric acid respectively or any two of them.It was found that these different anions can be induce-coadsorbed simultaneously on the silver surface through the protonated amino group of TU in the mixed acids ysstem.The coadsorption ability of the anions are in the order of So>NO?CLO at the potentials of at the potentials of The stability of TU on the surface of Agelectrode depends not only on the electrode potential but also on the nature of electrolyte anions coadsopbed.
文摘Mass-selected C60 beam produced by laser ablation was accelerated and bombarded the (0001) surface of highly oriented pyrolitic graphite and (111) surface of gold single crystal. The samples were characterized by STM. The STM images showed that, the deposited species collapsed and formed planar structure on the solid surface, but the collapsed species were not dissociated and well oriented on the surface. Both positive and negative C60 ions were observed in the desorption mass spectra, confirming that the species collapsed on the solid surface are still the C60 clusters.
基金Project supported by the National Natural Science Foundation of China (Grant Nas. 39370213 39770220+2 种基金 29773034)State Key Laboratory for Physical Chemistry of Solid Surfaces (Xiamen University)Natural Science Foundation of Hubei Province (Grant No
文摘Two kinds of DNA-modified electrodes were prepared by covalent and adsorptive immobilization of DNA onto self-assembled monolayers of 2, 2’-dithiodiethanol on gold electrodes and characterized by cyclic voltammetry, Xray photoelectron spectroscopy and scanning tunneling microscopy. The results suggest that the methods are satisfactory for the immobilization of DNA on electrodes.