Electrochemical oxidation of graphite anode in deionized water at galvanostatic mode is investigated. It is found that mellitic acid and graphite oxide colloid (>20 nm) are coexisted as main products, as identified by XRD and TEM, FTIR and XPS. They can be separated successfully through several procedures. A few amounts of graphene and graphene rolls are also appeared as co-products.

Photo-illumination effects have been measured for [CoIII-LS(phen)(3,5-DBSQ)(3,5-DBCat)]·C6H5Cl, where LS, phen, 3,5-DBSQ and 3,5-DBCat denote low-spin, 1,10-phenanthroline, 3,5-di-tert-butyl-1,2-semiquinonate and 3,5-di-tert-butyl-1,2-catecholate, respectively. When the Co compound was illuminated at 5 K, the magnetization value, μeff increased from 1.7 to 2.7μB. The UV-Vis absorption spectra after illumination show that the absorption band at around 800 nm, characteristic of the [CoII-HS(phen)(3,5-DBSQ)2] state (HS denotes high-spin), increased and the charge transfer band from 3,5-DBCat to 3,5-DBSQ at 2500 nm was reduced. IR spectra show that the CO stretching peak at 1280 cm−1 is significantly decreased. These results confirm that a photo-induced intra-molecular electron transfer, [CoIII-LS(phen)(3,5-DBSQ)(3,5-DBCat)]·C6H5Cl↔[CoII-HS(phen)(3,5-DBSQ)2]·C6H5Cl, was induced by 532 or 830 nm light. The relaxation kinetics of valence tautomerism was studied. For T≥25 K, kVT0=0.205 s−1 and Ea=110.38 cm−1. Below 25 K, the rate constant for the valence tautomeric relaxation as T approaches the 0 K, which suggests that tunneling is the predominant mechanism for the relaxation.

Multilayered assemblies of horseradish peroxidase (HRP) and bipolar quaternary ammonium salt (NC6BPC6N) were fabricated successfully by alternate deposition technique on the surface of quartz slides and gold electrode. The assembly process was monitored by ultraviolet–visible spectra on quartz slides. Cyclic voltammetry indicated that the gold electrode fabricated in this way had the function of reduction of hydrogen peroxide, in which methylene green transferred electrons successfully between the immobilized HRP and the electrode surface.