RESUMO
Achieving O2 photoreduction to H2O2 with high selectivity control and durability while using easily accessible catalyst requires new synthesis strategies. Herein, we propose an asymmteric Sb coordination active center strategy of introducing anthraquinone (AQ) and heptazine to form local N3 - Sb - O coordination by a rapid and simple explosive crystallization approach, resulting in a mesoporous conjugated heptazine-amide-AQ polymer coordinated Sb (HAAQ-Sb). It is demonstrated that the N3 - Sb - O coordination effectively suppresses the charge recombination and acts as the highly active site for O2 adsorption. Moreover, as-introduced AQ units initiate low-barrier hydrogen transfer through a reversible redox process that triggers highly-efficient H2O2 production. A superior apparent quantum yield of 20.2 % at 400 nm and a remarkable solar-to-chemical conversion efficiency of 0.71 % are achieved on the optimal HAAQ-Sb, which is the highest among C3N4-based photocatalysts at present. This asymmetric coordination concept and material design method provide new perspectives for the research of novel catalysts toward artificial photosynthesis.
RESUMO
Cyberchondria has become a severe health problem and a significant public concern. In addition to the impacts that cyberchondria involves, individual psychological and behavioral factors have been identified. However, the role of family function and the mediating and moderating mechanisms underlying these relations are not understood well, especially among adolescents. Based on family functioning and cognitive-behavioral theory, this study sought to examine whether family dysfunction was associated with cyberchondria, and a moderated mediation model was prepared as a means of exploring whether health anxiety was a mediator of relationships between family dysfunction and cyberchondria, as well as whether optimism moderated these mediating processes. A total of 2074 Chinese adolescents (mean = 15.08 years, SD = 1.79) reported their demographic information, family dysfunction, health anxiety, optimism, and cyberchondria. The findings showed that family dysfunction was positively related to cyberchondria. Moreover, health anxiety partially mediated the relationship between family dysfunction and cyberchondria. Finally, optimism moderated the interplay among health anxiety and cyberchondria. Consistent with the expectancy-value models, this positive relationship was weaker for adolescents with a higher level of optimism. These results suggest that it is vital to simultaneously consider individual and family factors as a means of understanding adolescent cyberchondria when performing cyberchondria intervention programs.
