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At a silver surface, surface-enhanced Raman scattering (SERS) technique along with the self-assembled monolayers (SAMs) method was performed to observe the adsorption behavior of AMT as a protective reagent for metals from corrosion. For 20 h of self-assembling, the time-dependent SERS spectra show that a stable AMT monolayers could form and the ultimate structure of AMT monolayers anchoring at the surface is in tilted mode via both sulfur atoms of thiol and thiadiazole ring with the nitrogen atom of amino. In situ SERS spectral electrochemical experiments indicate that the AMT monolayers experience an dynamic adsorption from a tilted fashion to a more horizontal mode for thiadiazole ring with the potential applied toward more negative voltage. Anticorrosive effect of the AMT monlayers has been ascertained by electrochemical impedance spectroscopy, which is in agreement with theoretic evaluation of the R(Q(R(QR))) mode.

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The highly efficient H 2 O 2 biosensor was fabricated on the basis of the complex films of hemoglobin (Hb), nano ZnO, chitosan (CHIT) dispersed solution and nano Au immobilized on glassy carbon electrode (GCE). Biocompatible ZnO-CHIT composition provided a suitable microenvironment to keep Hb bioactivity (Michaelis-Menten constant of 0.075 mmol L À1). The presence of nano Au in matrix could effectively enhance electron transfer between Hb and electrode. The electrochemical behaviors and effects of solution pH values were carefully examined in this paper. The (ZnO-CHIT)-Au-Hb/GCE demonstrated excellently electrocatalytical ability for H 2 O 2 . This biosensor had a fast response to H 2 O 2 less than 4 s and excellent linear relationships were obtained in the concentration range from1.94 Â 10 À7 to 1.73 Â 10 À3 mol L À1 with the detection limit of 9.7 Â 10 À8 mol L À1 (S/N ¼ 3) under the optimum conditions. Moreover, the stability and reproducibility of this biosensor were evaluated with satisfactory results.