The synergistic antimicrobial activities of three natural essential oils (i.e., clove bud oil, cinnamon oil, and star anise oil) with chitosan films were investigated. Cinnamon oil had the best antimicrobial activity among three oils against Escherichia coli , Staphylococcus aureus , Aspergillus oryzae , and Penicillium digitatum . The chitosan solution exhibited good inhibitory effects on the above bacteria except the fungi, whereas chitosan film had no remarkable antimicrobial activity. The cinnamon oil-chitosan film exhibited a synergetic effect by enhancing the antimicrobial activities of the oil, which might be related to the constant release of the oil. The cinnamon oil-chitosan film had also better antimicrobial activity than the clove bud oil-chitosan film. The results also showed that the compatibility of cinnamon oil with chitosan in film formation was better than that of the clove bud oil with chitosan. However, the incorporated oils modified the mechanical strengths, water vapor transmission rate, moisture content, and solubility of the chitosan film. Furthermore, chemical reaction took place between cinnamon oil and chitosan, whereas phase separation occurred between clove bud oil and chitosan.

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Phenylethynyl-substituted porphyrin (PE1) sensitizers bearing a nitro, cyano, methoxy, or dimethylamino phenylethynyl substituent were prepared to examine the electron-donating or -withdrawing effects of dyes on the photovoltaic performance of the corresponding dye-sensitized solar cells. The overall efficiencies of power conversion of the devices show a systematic trend Me 2 N-PE1 > MeO-PE1 > CN-PE1 > NO 2 -PE1, for which Me 2 N-PE1 has a device performance about 90% of that of a N719-sensitized solar cell under the same experimental conditions. The superior performance of Me 2 N-PE1 is attributed to the effective electron-donating property of the dye that exhibits broadened and red-shifted spectral features. According to frontier orbitals based on DFT calculations, the electrons are effectively injected from the dye to TiO 2 for Me 2 N-PE1 and MeO-PE1 upon excitation, but that driving force reverses for NO 2 -PE1. Electrochemical tests indicate that both LUMO and HOMO levels show a systematic trend Me 2 N-PE1 > MeO-PE1 > CN-PE1 > NO 2 -PE1, consistent with the trend of variation of the short-circuit currents in this series of sensitizers.

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In this present work, "killing two birds with one stone" strategy was performed for the electrochemical trace level detection and photocatalytic degradation of antibiotic drug chloramphenicol (CAP) using Ce(MoO) nanocubes/graphene oxide (CeM/GO) composite for the first time. The CeM/GO composite was synthesized via simple hydrothermal treatment followed by sonication process. The successful formation of CeM/GO composite was confirmed by several analytical and spectroscopic techniques. The CeM/GO composite modified glassy carbon electrode (GCE) showed excellent electrocatalytic activity toward the reduction of CAP in terms of decrease the potential and increase the cathodic peak current in comparison with different modified and unmodified electrodes. The electrocatalytic reduction of CAP based on the CeM/GO modified GCE exhibited high selectivity, wide linear ranges, lower detection limit, and good sensitivity of 0.012-20 and 26-272 μM, 2 nM ,and 1.8085 μA μM cm, respectively. Besides, when CeM/GO/GCE was used to analyze the CAP in real samples, such as honey and milk, the satisfactory recovery results were obtained. On the other hand, the CeM/GO composite played excellent catalyst toward the photodegradation of CAP. The obtained results from the UV-vis spectroscopy clearly suggested that CeM/GO composite had high photocatalytic activity compared to pristine Ce(MoO4) nanocubes. The degradation efficiency of CeM/GO toward CAP is observed about 99% within 50 min under visible irradiation and it shows a good stability by observing the reusability of the catalyst. The enhanced photocatalytic performance was attributed to the increased migration efficiency of photoinduced electrons and holes.