C-doped ZnO decorated with Au nanoparticles constructed from the metal-organic framework ZIF-8 for photodegradation of organic dyes.

Recently, engineering metal-organic frameworks (MOFs) into metal oxides by solid state thermal decomposition has attracted wide attention for photocatalytic applications. Here, a series of C-doped ZnO materials decorated with Au nanoparticles (Au/C-ZnO) were constructed via controlled pyrolysis of ZIF-8 adsorbing different amounts of HAuCl4·4H2O. In this pyrolysis process, ZIF-8 was transformed into C-doped ZnO according to the EDX and XPS analysis. Meanwhile, HAuCl4·4H2O was transformed into Au nanoparticles that were uniformly dispersed on the surface of C-ZnO as seen in TEM images. The photocatalytic activity of as-prepared catalysts was evaluated by the degradation of methyl orange under UV-vis light irradiation. It was found that the photocatalytic activity of Au/C-ZnO was better than C-ZnO and pure ZnO. Furthermore, Au/C-ZnO exhibited high photocatalytic stability. After three consecutive cycles, there was no noticeable deactivation in the reaction. This unusual photocatalytic activity was attributed to the synergistic effect of C-doping and Au NPs.

Constructing ZIF-8 derived C-ZnS/ZnMoO4@MoS2 and C-ZnS/MoS2 nanocomposites using a simple one-pot strategy to enhance photocatalytic degradation activity.

Efficient C-ZnS/ZnMoO4@MoS2 and C-ZnS/MoS2 nanocomposite photocatalysts, using ZIF-8 derived C-ZnO as a precursor were successfully synthesized using a simple one-pot procedure. This is the first application that involves transforming ZIF-8 into C-ZnMoO4 for photocatalysis. The C-ZnS/ZnMoO4@MoS2 and C-ZnS/MoS2 heterostructures were characterized by X-ray diffraction, UV-vis, X-ray photoelectron spectroscopy, electrochemical impedance spectroscopy, photocurrent measurements, scanning electron microscopy and transmission electron microscopy. The ZM2 sample of C-ZnS/ZnMoO4@MoS2 exhibited enhanced photocatalytic activity of about 2.9 times as high as that of ZIF-8 derived C-ZnO in the reduction of tetracycline hydrochloride, and also showed obvious photocatalytic activity 1.81 and 3.33 times as high as that of a ZM3 sample of C-ZnS/MoS2 and ZIF-8 derived C-ZnO in the degradation of RhB, respectively. The improved photodegradation activity is a result of the heterogenous structure and the tighter contact between C-ZnS and C-ZnMoO4 compared with the physical contact of general heterogenous photocatalysts. The C-ZnS/ZnMoO4@MoS2 heterostructure photocatalyst is expected to be a new type of nanomaterial for the degradation of pollutants from wastewater.

Evaluation of effectiveness of integrated intervention program in improving drug addicts' psychological health.

OBJECTIVE: To investigate the social mental state of drug addicts in a compulsive drug abuse treatment center; evaluate the effectiveness of integrated program for the prevention of abuse relapse and improvement of drug addicts' psychological health. METHODS: The study subjects were addicts from the Wuhan Compulsive Drug Abuse Treatment Center between October 2003 and June 2004, who satisfied the inclusion criteria. A non-randomized control-intervention study design was adopted. Volunteers willing to take part in intervention were put into the intervention group with their full awareness and willingness to prevent drug abuse relapse. The control group was composed of the addicts who were willing to prevent relapse and to be followed up after their discharge. RESULTS: The effectiveness of the integrated intervention program in promoting addicts' psychological health: before the intervention, the scores of Self-Rating Anxiety Scale (SAS), the positive and negative dimensionalities of Simple Coping Style Questionnaire (SCSQ) and Chinese Perceived Stress Scales (CPSS) had no significant differences between the intervention group and the control group. After the intervention, except that the SCSQ's positive dimensionality in the intervention group was significantly higher than that in the control group, other indices in the intervention group were lower. Before and after the intervention, the psychological health level in both the groups was lower than that in the normal population; there were significant differences between addicts and normal subjects in regards with all of the indices above. CONCLUSION: Drug abuse was associated closely with addicts' social mental factors. The integrated intervention program can alleviate anxiety and stress, reduce co-morbid mental disorders and effectively improve their coping style. In conclusion, the program can promote addicts' psychological health significantly.