CuSCN has been widely considered a promising candidate for low-cost and high-stable hole transport material in perovskite semitransparent solar cells (STSCs). However, the low conductivity of the solution-processed CuSCN hole transport layer (HTL) hinders the hole extraction and transport in devices, which makes it hard to achieve devices with high performance. Herein, we report a facile additive engineering approach to optimize the p conductivity of CuSCN HTLs in perovskite STSCs. The n-butylammonium iodide additive facilitates the formation of Cu2+ and generates more Cu vacancies in the CuSCN HTL. This realizes a significant enhancement of the hole concentration and p conductivity of the film. Moreover, the additive improves the solubility of the CuSCN precursor solution and results in a uniform coverage on the perovskite active layer. Therefore, the perovskite STSC with a high power conversion efficiency (PCE) of 19.24% has been achieved, which is higher than that of the spiro-OMeTAD (18.83%) and CuSCN (17.45%) counterparts. In addition, the unencapsulated CuSCN-based device retains 87.5% of the initial PCE after 20 days in the ambient atmosphere.
Vesicular stomatitis virus (VSV) has been reported to induce apoptosis and the onset of apoptosis may play an important role in virus-associated diseases. This study was conducted in order to investigate the protective effect of the herbal constituent allicin on VSV-induced apoptosis in the human monocyte line THP-1, human T lymphocytic leukemia cell line MT-2 and human amniotic cell line WISH and to determine the possible molecular mechanism involved. The THP-1, MT-2 and WISH cells were incubated with VSV in the absence or presence of different doses of allicin (10, 25 and 50 μg/ml). To study apoptosis, the cells were assessed by MTT and annexin V-propidium iodide double-staining flow cytometry. To investigate the molecular mechanism by which allicin regulates VSV-induced THP-1, MT-2 and WISH cell apoptosis, the expression of active cleavage products of caspases 3, 6, 7 and 9 and NF-κB was analyzed by western blotting. Our results indicated that allicin did not affect the adhesion and entry of VSV into THP-1, MT-2 or WISH cells. Using different concentrations of allicin, a dose-dependent protective effect on cell apoptosis was observed. In addition, the VSV-induced expression of active cleavage products of caspases 3, 6, 7 and 9 and NF-κB in THP-1, MT-2 and WISH cells was also significantly reduced by allicin at the protein level. We concluded that allicin protects THP-1, MT-2 and WISH cells from VSV-induced apoptosis by inhibiting the activation of caspases 3, 6, 7 and 9 and NF-κB, thereby suggesting a potential protective effect for allicin against virus-associated diseases. Key words: Allicin, vesicular stomatitis virus (VSV), apoptosis, caspases, NF-κB.
The single‐crystalline silicon solar cell with tunnel oxide passivating poly‐Si contact (TOPCon) has developed into one of the most promising and high‐performance n‐type Si‐based solar cells in their mass production way because of its high conversion efficiency and robustness. Owing to its unique device structure, TOPCon shows superior advantages over amorphous Si‐based heterojunction one (HJT) in developing high‐performance monolithic perovskite/silicon tandem solar cell because TOPCon may have better tolerance than HJT to the particle bombardments and plasma fluorescence irradiations in the sputtering deposition process of transparent conductive oxide (TCO) recombination layer. Herein, bathocuproine (BCP):silver complex is introduced as a buffer recombination contact between TCO and poly‐SiC X , to modulate the tunneling junction between perovskite/TOPCon. Depending on fine film thickness and derived energy level tuning, BCP:Ag buffer layer can effectively prevent the sputter bombardments and passivate the interface of TCO/poly‐SiC X (n)/SiO X contact, as well as enhancing electron transport. As a result, a certified conversion efficiency of 25.84% is achieved in the monolithic perovskite/TOPCon silicon tandem solar cell. This work definitely paves a new and promising way to develop high‐performance monolithic perovskite/c‐Si tandem solar cells.
Gastric cancer (GC) is one of the most common malignancies around the world, and the incidence of GC is increasing in the past decades. In addition to genetic modifications, epigenetic alterations catalyzed by DNA methyltransferases (DNMTs) are a well-characterized epigenetic hallmark in gastric cancer. Nowadays, DNA methylation landscape is essential for maintaining the silence of tumor suppressor genes (TSGs). As an important group of peptide, TFF family has been confirmed to function as a TSG in various kinds of cancers. However, whether TFFs could be modified by DNA methylation in gastric cancer remains unknown. In this study, we initially screened out two expression profiles about GC from Gene Expression Omnibus (GEO) database. The higher expressions of TFF1 and TFF2 were observed in GC tumor tissues than normal tissues. Additionally, we illustrated that the expressions of TFF1/TFF2 were associated to the overall survival (OS) and tumor free survival (TFS) of GC patients via through the Kaplan-Meier analysis. Subsequently, the integrative analysis was performed to estimate the DNA methylation level of each site in TFF1/TFF2 CpG islands. Importantly, our findings indicated that hyper-methylation of cg01886855 and cg26403416 were separately responsible for the downregulation of TFF1 and TFF2 in GC samples. Besides, utilizing the gain of function assay, we demonstrated that TFF1/TFF2 could suppress the proliferation of GC cells. Based on these results, We identified that TFF1 and TFF2 acted as the putative tumor suppressors in gastric cancer, which suggested that TFFs could be two candidate biomarkers for predicting tumor recurrence in gastric cancer patients. Furthermore, these findings highlight a potential therapeutic approach in targeting the TFFs for the treatment of gastric cancer.
Self‐assembled monolayers (SAMs) have emerged as effective carrier transport layers in perovskite (PVK) solar cells because of their unique ability to manipulate interfacial property, as well as simple processing and scalable fabrication. However, the defects and pinholes derived from their sensitive adsorption process inevitably deteriorate the final device performance. Herein, a sputtered nickel oxide (NiO x ) interlayer is used as a seed layer to promote the adsorption of the [2‐(3,6‐dimethoxy‐9H‐carbazol‐9‐yl)ethyl]phosphonic acid (MeO‐2PACz) SAM on the indium tin oxide (ITO) substrate. The promoted adsorption is attributed to the enhanced tridentate binding between MeO‐2PACz and NiO x relative to the conventional bidentate binding between MeO‐2PACz and ITO. In addition, the NiO x modification can simultaneously improve the passivation ability and hole‐selectivity of the MeO‐2PACz, provide a favorable energy‐level alignment at the ITO/PVK interface, and prevent a direct contact between PVK and ITO. As a consequence, this NiO x ‐seeded MeO‐2PACz hole transport layer enables a significantly enhanced power conversion efficiency of 19.9% in comparison with 18.4% of the control device. This work provides an effective strategy to improve the performance of the SAM‐based photoelectric device.
This paper presents an optimized Concentrating Photovoltaic/Thermal system based on the direct absorption collection concept. In this system, working fluid water and solar cell separately utilizes solar radiation at different wavelengths to achieve photothermal conversion and photoelectric conversion. The system avoids the complicated fabrication technique in conventional CPV/T systems. The thermal unit has no temperature limitation from the PV module. As the incident solar irradiance increases from 800 W/m 2 to 3,600 W/m 2 , the system can produce high grade heat, almost without sacrificing electrical efficiency (around 8.9% to 10.4%), and the total exergetic efficiency of the system increases from 12.8% to 18.4%.
CsPbI2Br perovskite solar cells (PSCs) based on carbon electrodes (CEs) are considered to be low-cost and thermally stable devices. Nevertheless, the insufficient contact and energy level mismatch between the CsPbI2Br layer and CE hinder the further enhancement of the cell efficiency. Herein, a carbon black (CB) interlayer was introduced between the perovskite layer and CE. The hole extraction was facilitated due to the larger contact area and suitable energy band alignment in the CsPbI2Br/CB interface. Further investigation indicated the diffusion of CB nanoparticles from the CE or CB layer to the CsPbI2Br film after a certain period of time. We disclosed the formation of a CB-CsPbI2Br bulk heterojunction structure due to the carbon diffusion, which resulted in an efficiency enhancement. As a result, a record efficiency of 13.13% is achieved for carbon-based inorganic PSCs. This work also reveals that the diffusion of CB nanoparticles in CB-containing PSCs is universal and inevitable, although this kind of diffusion results in the enhancement of cell efficiency.
Compared with the single‐junction perovskite solar cells, the perovskite/perovskite tandem solar cells have the advantages of lower cost and higher power conversion efficiency (PCE). Herein, both two‐terminal (2‐T) and four‐terminal (4‐T) perovskite/perovskite tandem solar cells with all‐inorganic perovskite as the top cell absorption layer and narrow bandgap perovskite MASn 0.5 Pb 0.5 I 3 material as the bottom cell absorption layer are studied. To effectively improve the photon absorption ratio and performance of the 4‐T tandem device, both reflection and parasitic absorption should be reduced. Afterward, by optimizing the doping concentration of the carrier transport layer, a 4‐T all‐perovskite tandem solar cell with a high PCE of 30.45% is obtained. For the 2‐T all‐perovskite tandem device, the all‐inorganic perovskites with different halogen components (CsPbI 3− x Br x , 0 ≤ x ≤ 3) are used as the absorption layer of the top cell, respectively. Through the optimization of the current matching of the subcell, the photoelectric field distribution, the parasitic absorption of the device, etc., an optimal PCE of 27.86% is obtained based on 2‐T CsPbI 2 Br/MASn 0.5 Pb 0.5 I 3 tandem device. This study provides a guide for achieving high performance perovskite/perovskite tandem solar cells.