| Liquid/liquid (L/L) interface, or oil/water interface (W/O), refers the interface between two immiscible electrotlyte solutions (ITIES). Electrochemistry at liquid/liquid interface is gradually becoming an important branch of Electrochemisty and Electroanalytical Chemistry because it can study not only the electron tansfer, but also the non-redox ion transfer. The charge transfer across such interface play important roles in better understanding the ion selective electrode, phase transfer or interfacel catalysis, drug delivery in pharmacology, biological membrane phenomena and so forth. In this thesis, the organic metal charge transfer complexes AgTCNQ and CuTCNQ were synthesized by using the electrochemcial methodologies of L/L interface. The main results are as follows:(1) Nanostructured Ag/AgTCNQ Schottky junctions composite PET membrane were fabricated at the PET supported W/1,2-DCE interface. One side of the composite PET film is Ag and the other side is AgTCNQ nanorods. The XRD result indicated that the AgTCNQ nanorods are orthorhombicwith the lattice parameters:a=6.95A, b=16.69A and c=17.45A. By assembling the composite film in an all-in-solid-state electrolytic cell, the cyclic voltammograms of Ag/AgTCNQ Schottky junctions were obtained for the first time. The faradic peak current is in proportion to the scanning rate and the integrate charge of the anodic peak is equal to that of the cathodic peak, which shows the typical characteristics of solid-state electrochemistry. The values of a and j0are obtained from Tafel experiment as0.533and2.21×10-6A·-cm-2which indicate the excellent chemical reversibility and stability. Moreover, the switch effect between low-resistance and high-resistance was observed, which indicates that the Ag/AgTCNQ composite PET membrane has potential applications in electronic devices.(2) CuTCNQ microneedles was synthesised by a novel electrosynthetic method, which was based on the charge coupling transfer across interface. The property of electrochemistry amd electrical switching behavior of CuTCNQ was disscussed. Cu2+is too hydrophilic to transfer across W/1,2-DCE interface in the experimental potential region. When TCNQ was reduced at the HOPG/1,2-DCE interface in1,2-DCE phase, Cu2+cations should transfer from the aqueous phase into1,2-DCE phase to maintain the electric neutrality of the system and react with TCNQ-to form CuTCNQ. The CuTCNQ is needle-like crystal with the length and width of0.2-0.7μm and3-10μm. The CuTCNQ microneedles on the surface of HOPG electrode was sandwiched between a copper foil and an aluminum foil to construct an all-in-solid-state electrochemical cell. The solid-state voltammetric and Tafel behavior were observed. The values of α and j0are obtained as0.4and2.22×10-6A cm-2which predict an exellent chemical reversibility and stability. Similar to AgTCNQ, the abrupt change of resistance at certain critical potentials indicates that the obtained CuTCNQ microneedles are qualified to be used as material for electronic switches.(3) Comparing the solid-state voltammetric behaviors of CuTCNQ and Ag/AgTCNQ, it should be noted that the contact resistance between current collector and functional materials could be eliminated by the Ag/AgTCNQ Schottky junctions. The molecular mechanism of the electronic behavior is actually the charge transfer across the schottky junctions. Therefore, the construction of the electrochemical interface is essential for the electronic performance of the functional nanomaterials. |
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