ABSTRACT
The energy band structure, density of states, and optical properties of monolayers of MoS2 doped with alkaline earth metals (Be/Mg/Ca/Sr/Ba) are systematically studied based on first principles. The results indicate that all the doped systems have a great potential to be formed and structurally stable. In comparison to monolayer MoS2, doping alkaline earth metals results in lattice distortions in the doped system. Therefore, the recombination of photogenerated hole-electron pairs is suppressed effectively. Simultaneously, the introduction of dopants reduces the band gap of the systems while creating impurity levels. Hence, the likelihood of electron transfer from the valence to the conduction band is enhanced, which means a reduction in the energy required for such a transfer. Moreover, doping monolayer MoS2 with alkaline earth metals increases the static dielectric constant and enhances its polarizability. Notably, the Sr-MoS2 system exhibits the highest value of static permittivity, demonstrating the strongest polarization capability. The doped systems exhibit a red-shifted absorption spectrum in the low-energy region. Consequently, the Be/Mg/Ca-MoS2 systems demonstrate superior visible absorption properties and a favorable band gap, indicating their potential as photo-catalysts for water splitting.
ABSTRACT
Aim To explore the anti-psoriatic effects of honokiol on the mouse model induced by imiquimod and the underlying mechanism. Methods The mice were randomly divided into control group, model group, liposome solvent control group, dexamethasone positive group and honokiol high, medium, low dose groups. The progress of the disease was observed by the psoriasis area and severity index (PASI). The morphological changes of the skin cells were observed by HE staining, and epidermis thickness was meas-ured. The expression of IL-17, IL-23, JAK, STAT3, TNF-α and NF-κB was semi-quantitively analyzed by immunohistochemistry. Results Compared to model group, the scaling and thickness of honokiol treated groups were alleviated. Inflammatory infiltration and micro abscess were reduced. The expressions of IL-17, IL-23, JAK, STAT3, TNF-α and NF-κB in model group were higher than those in honokiol-high and honokiol-medium group in a dose-dependent manner. Conclusion Honokiol can inhibit imiquimod-induced psoriasis-like lesions in mice by inhibiting the IL-17/IL-23 inflammatory axis.
