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It is of great significance to design an efficient heterostructure for photocatalytic hydrogen production to solve the energy shortage and environmental crisis. In this letter, we investigate the structure, electron of interface, optical, charge transfer, and photocatalytic mechanism of three different ZnIn2S4/α-In2Se3 heterostructures by hybrid density functional calculation. It is interesting that the presence of an external electric field not only can change the bandgap but also can modulate the band alignment type. Among them, heterostructure A belongs to type II heterostructure, and heterostructure B and C belong to a Z-scheme heterostructure. Especially in heterostructure C, the electrons deposited on CBM of a ZnIn2S4 monolayer will play an important role in the hydrogen production process. Meanwhile, the small bandgap of ZnIn2S4/α-In2Se3 Z-scheme heterostructures enables it to obtain a wide light absorption range. Therefore, this study contributes to the design of a novel and potential Z-scheme heterostructure photocatalyst with broad application prospects in both electronic and optoelectronic fields. [ABSTRACT FROM AUTHOR]

Background: Reduction of inflammatory damage and inhibition of nucleus pulposus (NP) apoptosis are considered to be the main effective therapy idea to reverse the intervertebral disc degeneration (IDD) and alleviate the chronic low back pain. The adenosine A2A receptor (A2AR), as a member of G protein-coupled receptor families, plays an important role in the anti-inflammation and relieving pain. So far, the impact of A2AR on IDD therapy is unclear. The aim of this study was to explore the role of Adenosine A2A receptor (A2AR) in the intervertebral disc degeneration (IDD) and clarify potential mechanism. Materials and methods: IL-1β and acupuncture was used to establish IDD model rats. A2AR agonist CGS-21680 and A2AR antagonist SCH442416 were used to investigate the therapeutical effects for IDD. Histological examination, western blotting analysis and RT-PCR were employed to evaluate the the association between A2AR and cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway. Results: A2AR activity of the intervertebral disc tissues was up-regulated in feedback way, and cAMP, PKA and CREB expression were also increased. But in general, IL-1β-induced IDD promoted the significant up-regulation the expression of inflammatory factors. The nucleus pulposus (NP) inflammation was exacerbated in result of MMP3 and Col-II decline through activating NF-κB signaling pathway. A2AR agonist CGS-21680 exhibited a disc protective effect through significantly increasing A2AR activity, then further activated cAMP/PKA signaling pathway with attenuating the release of TNF-α and IL-6 via down-regulating NF-κB. In contrast, SCH442416 inhibited A2AR activation, consistent with lower expression levels of cAMP and PKA, further leading to the acceleration of IDD. Conclusions: The activation of A2AR can prevent inflammatory responses and mitigates degradation of IDD thus suggest a potential novel therapeutic strategy of IDD. [ABSTRACT FROM AUTHOR]

The photoelectric conversion efficiency of CsSnBr3 solar cells only reached 3.04% due to the insufficient separation of photogenerated charge and the short lifetime of the carriers. Herein, interfacial electronic properties and photovoltaic performance of the CsSnBr3/SnS2 heterostructure without and with Bromine vacancy defects are studied using a hybrid density functional method. We find that strong coupling and hybridization of interfacial electronic states in the CsSnBr3/SnS2 heterostructure can lead to a narrowing band gap, which induces excellent optical absorption. Bromine vacancies are introduced into the CsSnBr3/SnS2 heterostructure to provide more electrons and modulate its physicochemical properties. Excitingly, the charge transfer forms a stronger built-in electric field in the VBr-CsSnBr3/SnS2 heterostructure, which can effectively promote the charge transfer between VBr-CsSnBr3 (001) and the SnS2 monolayer complying with a Z-scheme pathway. The coupling interface and vacancy defects improve the photovoltaic performance of CsSnBr3. This study offers a novel design idea for CsSnBr3-based perovskite materials in photovoltaic applications. [ABSTRACT FROM AUTHOR]