Recyclable V2O5/g-C3N4 Heterojunction-Catalyzed Visible-Light-Promoted C3-H Trifluoromethylation of Quinoxalin-2-(1H)-ones.

A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1H)-ones was established using a Z-scheme V2O5/g-C3N4 heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1H)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V2O5/g-C3N4 catalyst could be reused five times with a slight loss of catalytic activity.

Highly sensitive and repeatable recording photopolymer for holographic data storage containing N-methylpyrrolidone.

The low photosensitivity of phenanthraquinone-doped poly(methyl methacrylate) (PQ/PMMA) severely limits its recording speed for holographic data storage. A high-performance holographic recording medium based on a unique combination of N-methylpyrrolidone (NMP) regulated PQ/PMMA has been developed. A NMP-PQ/PMMA photopolymer with high sensitivity, high diffraction efficiency and negligible volume shrinkage was successfully fabricated by tuning the composition of the PMMA matrix by varying the ratio of NMP to monomers. The photosensitivity is increased by 6.9 times (from 0.27 cm J-1 to 1.86 cm J-1), the diffraction efficiency is increased from 60% to > 80%, and volume shrinkage is decreased by a factor of 2 (from 0.4% to 0.2%). Further investigation revealed that the addition of NMP significantly reduced the molecular weight of PMMA and increased the amount of MMA residuals, while also improving the solubility of PQ molecules. More interestingly, for the first time, the NMP-PQ/PMMA material could record data information repeatedly at least 6 times. The present study elucidates that the introduction of NMP not only modulates the molecular weight of PMMA but also enables the residual monomer MMA to more easily combine with PQ to form a photoproduct for improved holographic performance.

Synergistic design of a semi-hollow core-shell structure and a metal-organic framework-derived Co/Zn selenide coated with MXene for high-performance lithium-sulfur batteries.

Lithium-sulfur batteries have garnered significant interest as potential energy storage systems for the future, owing to their remarkable theoretical specific capacity (1675 mA h g-1) and energy density (2600 W h kg-1). However, their development has been severely impeded by several challenges, including the low intrinsic conductivity of sulfur, volume expansion issues, and the polysulfide shuttle effect. To address these issues, polar metal compounds with nanostructures featuring hollow shells and catalytic functions have emerged as promising materials for designing advanced lithium-sulfur batteries. In this study, bimetallic selenides with varying degrees of hollowness are synthesized using a tannic acid etching and selenization strategy. By comparing the electrochemical characteristics of composite electrodes with different degrees of hollowness, an optimal semi-hollow core-shell structure is identified, implying that reasonable structural designing of metal compounds carries immense importance in improving electrochemical reactions. Moreover, the appropriate degree of hollowness effectively mitigates volume expansion issues associated with the sulfur cathode. Consequently, bimetallic selenides with a hollow core-shell structure coated with conductive MXene material exhibit superior electrochemical performance. The synergistic effect achieved through the judicious design of the hollow core-shell structure and the utilization of polar metal compounds has proved instrumental in enhancing the redox kinetics of lithium-sulfur batteries. As such, this research presents a novel avenue for the development of high-performance lithium-sulfur batteries.

Transcriptomic, 16S ribosomal ribonucleic acid and network pharmacology analyses shed light on the anticoccidial mechanism of green tea polyphenols against Eimeria tenella infection in Wuliangshan black-boned chickens.

BACKGROUND: Eimeria tenella is an obligate intracellular parasitic protozoan that invades the chicken cecum and causes coccidiosis, which induces acute lesions and weight loss. Elucidating the anticoccidial mechanism of action of green tea polyphenols could aid the development of anticoccidial drugs and resolve the problem of drug resistance in E. tenella. METHODS: We constructed a model of E. tenella infection in Wuliangshan black-boned chickens, an indigenous breed of Yunnan Province, China, to study the efficacy of green tea polyphenols against the infection. Alterations in gene expression and in the microbial flora in the cecum were analyzed by ribonucleic acid (RNA) sequencing and 16S ribosomal RNA (rRNA) sequencing. Quantitative real-time polymerase chain reaction was used to verify the host gene expression data obtained by RNA sequencing. Network pharmacology and molecular docking were used to clarify the interactions between the component green tea polyphenols and the targeted proteins; potential anticoccidial herbs were also analyzed. RESULTS: Treatment with the green tea polyphenols led to a reduction in the lesion score and weight loss of the chickens induced by E. tenella infection. The expression of matrix metalloproteinase 7 (MMP7), MMP1, nitric oxide synthase 2 and ephrin type-A receptor 2 was significantly altered in the E. tenella infection plus green tea polyphenol-treated group and in the E. tenella infection group compared with the control group; these genes were also predicted targets of tea polyphenols. Furthermore, the tea polyphenol (-)-epigallocatechin gallate acted on most of the targets, and the molecular docking analysis showed that it has good affinity with interferon induced with helicase C domain 1 protein. 16S ribosomal RNA sequencing showed that the green tea polyphenols had a regulatory effect on changes in the fecal microbiota induced by E. tenella infection. In total, 171 herbs were predicted to act on two or three targets in MMP7, MMP1, nitric oxide synthase 2 and ephrin type-A receptor 2. CONCLUSIONS: Green tea polyphenols can directly or indirectly regulate host gene expression and alter the growth of microbiota. The results presented here shed light on the mechanism of action of green tea polyphenols against E. tenella infection in chickens, and have implications for the development of novel anticoccidial products.

Macrophage MVP regulates fracture repair by promoting M2 polarization via JAK2-STAT6 pathway.

OBJECTIVE: Major vault protein (MVP) is vital in various macrophage-related inflammatory diseases. However, the effects of MVP on macrophage polarization during fracture repair are still unknown. METHODS: We used Mvpflox/floxLyz2-Cre mice (myeloid-specific MVP gene knockout, abbreviated as MacKO) and Mvpflox/flox (abbreviated as MacWT) mice to compare their fracture healing phenotype. Next, we traced the changes in macrophage immune status in vivo and in vitro. We further explored the effects of MVP on osteogenesis and osteoclastogenesis. Finally, we re-expressed MVP in MacKO mice to confirm the role of MVP in fracture healing. RESULTS: The lack of MVP in macrophages impaired their transition from a pro-inflammatory to an anti-inflammatory phenotype during fracture repair. The increased secretion of pro-inflammatory cytokines by macrophages promoted their osteoclastic differentiation and impaired BMSC osteogenic differentiation, ultimately leading to impaired fracture repair in MacKO mice. Last, adeno-associated virus (AAV)-Mvp tibial injection significantly promoted fracture repair in MacKO mice. CONCLUSIONS: Our findings showed MVP has a previously unknown immunomodulatory role in macrophages during fracture repair. Targeting macrophage MVP may represent a novel therapeutic method for fracture treatment.

Visible-Light-Induced Annulation of Iodonium Ylides and 2-Isocyanobiaryls to Access 6-Arylated Phenanthridines.

A 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4-CzIPN)-photocatalyzed cascade arylation/cyclization reaction of 2-isocyanobiaryls and iodonium ylides was established for the synthesis of 6-arylated phenanthridines. This is the first example of employing iodonium ylides as aryl radical sources in a visible-light-induced radical cascade cyclization reaction.

Drug-eluting bead transarterial chemoembolization could improve the hepatic hemodynamics of patients with unresectable hepatocellular carcinoma: a retrospective cohort study.

Background: Transarterial chemoembolization (TACE) is widely used for patients with unresectable hepatocellular carcinoma (HCC); however, previous studies have demonstrated that conventional TACE (cTACE) might affect hepatic hemodynamics, which both associate with liver cirrhosis and survival. Drug-eluting bead TACE (DEB-TACE) improves treatment efficacy and safety, but its effects on the hepatic hemodynamics of HCC patients with cirrhosis remain unknown. Methods: This retrospective cohort study included unresectable HCC patients treated with DEB-TACE from April 2018 to September 2020, who had limited tumor burden and liver function. The hepatic hemodynamics was measured by hepatic venous pressure gradient (HVPG) using occlusion balloon catheter before and after treatment. Baseline characteristics of demography, laboratory (tumoral and liver-function) and hepatic hemodynamics were compared between patients with and without clinically significant portal hypertension (CSPH). Laboratory examination and imaging assessments were performed 4-6 weeks; overall survival (OS) was defined as the time from DEB-TACE initiation until death or last follow-up. Results: Twenty-four eligible consecutive HCC patients were included, with a median age of 58.0 years and 54.2% in Child-Pugh A class. During a median follow-up of 9.8 months, median OS for the whole cohort of patients reached 10.0 months. Kaplan-Meier survival curves and Cox regression analyses demonstrated that age >60 years, ascites, Eastern Cooperative Oncology Group (ECOG) score of 1, Child-Pugh B class, Model for End-Stage Liver Disease (MELD) score >10, and albumin (ALB) <35 g/L were prognostic factors for decreased OS (P<0.05). Importantly, hepatic hemodynamics were significantly improved in patients after treatment with DEB-TACE (7.5 vs. 5.3 mmHg of HVPG, P<0.001), especially for those with CSPH (13.6 vs. 10.2 mmHg of HVPG, P=0.014). Conclusions: DEB-TACE can improve hepatic hemodynamics in HCC patients, especially those with CSPH. Combing these findings with its effects on tumor, DEB-TACE might be more suitable for HCC patients with cirrhosis.

Photosynthesis of 3-Alkylated Coumarins from Carboxylic Acids Catalyzed by a Na2S-Based Electron Donor-Acceptor Complex.

A simple and practical electron donor-acceptor (EDA) strategy to synthesize various 3-alkylated coumarins from easily available coumarins and naturally abundant carboxylic acids under photocatalyst-, oxidant-, and additive-free and mild conditions is reported. Using Na2S as the catalytic electron donor, a series of primary, secondary, and tertiary carbon radicals can be efficiently generated, and the EDA complex can be regenerated without an alkaline additive.

Omentin-1 promotes mitochondrial biogenesis via PGC1α-AMPK pathway in chondrocytes.

OBJECTIVE: Omentin-1 is a newly discovered metabolic regulatory adipokine. Studies have shown that omentin-1 possesses pleiotropic effects in different types of cells. This study aims to investigate the regulation by omentin-1 on mitochondrial biogenesis in chondrocytes. METHODOLOGY: C-28/I2 chondrocytes were treated with omentin-1 (150 and 300 ng/ml) for 24 h. The expression of mitochondrial regulators, markers and the DNA copy was assessed. The mitochondrial morphology was observed by electron microscopy. The mitochondrial respiratory rate and ATP production in chondrocytes were measured by cell lysates. RESULTS: Omentin-1 treatment up-regulated PGC-1α, NRF-1 and mitochondrial transcription factor A (TFAM) in cultured chondrocytes, indicating that omentin-1 could be involved in the regulation of mitochondrial function. Omentin-1 promoted mtDNA/nDNA and four mitochondrial genes (Tomm20, Tomm40, Timm9 and Atp5c1), mRNA transcripts as well as two mitochondrial protein expressions (SDHB and MTCO1). At a cellular level, omentin-1 enhanced the mitochondrial respiratory rate and ATP production. Mechanistically, we proved that omentin-1 increased AMPKα activation, and the blockage of AMPKα by its inhibitor compound C abolished the inductive effect of omentin-1 on PGC1α expression and mtDNA/nDNA ratio, indicating that the effect of omentin-1 is dependent on AMPKα activation. CONCLUSION: Omentin-1 is a positive regulator of mitochondrial biogenesis in chondrocytes, and its action is dependent on the AMPK-PGC1α pathway. This study, therefore, implies that omentin-1 has the potential to remedy chondrocyte damage in the prevention and treatment of osteoarthritis.

A randomized controlled trial to verify the irrigation of salivary glands in relieving xerostomia in patients with Sjögren's syndrome.

Objective: To verify the effect of triamcinolone acetonide (TA) and major salivary glands saline irrigation on relieving xerostomia in Sjögren's syndrome (SS) patients. Methods: The enrolled 49 SS patients were randomly assigned to the control group (no irrigation, n=16), saline group (irrigation with saline, n=17) and TA group (irrigation with TA, n=16). Fourteen cases of each group were treated differently but received the same examinations. The examinations include unstimulated whole saliva flow (UWS), chewing-stimulated whole saliva flow (SWS), citric acid-stimulated parotid flow (SPF), Clinical Oral Dryness Score (CODS), Xerostomia Inventory (XI) and EULAR SS Patient Reported Index (ESSPRI) of 1 week before irrigation (T0) and 1 week(T1), 8 weeks (T8), 16 weeks (T16) and 24 weeks (T24) after major salivary irrigation. Results: Each group had 14 cases with completed follow-ups. Both TA and saline irrigation of major salivary glands resulted in higher SWS and SPF of T8, T16 and than those at T0. ESSPRI (oral dryness domain) of T8, T16 and T24 were significantly lower than that at T0, respectively (P < 0.05). SWS and SPF of T8, T16 and T24 in the saline group were significantly higher than in the control group (P< 0.05). XI and ESSPRI (oral dress domain) of T8, T16 and T24 in the saline group were significantly lower than those in the control group, respectively (P< 0.05). SWS and SPF of T16 and T24 in the TA group were significantly higher than in the control group (P< 0.05). All cases with completed follow-up in TA and saline groups were divided into responders and non-responders. Compared with responders, the UWS, SWS, SPF and CODS of T0 in non-responders were significantly increased (P<0.05). Compared with responders, the XI and ESSPRI of T0 in non-responders were significantly decreased (P<0.05). Conclusion: The irrigation of major salivary glands by TA and saline relieve xerostomia in SS patients. Patients with non-severe xerostomia (responders) have better relief after irrigation than patients with severe xerostomia (non-responders). Clinical Trial Registration: www.chictr.org.cn, identifier (ChiCTR210052314).

Electrocatalytic three-component synthesis of 4-halopyrazoles with sodium halide as the halogen source.

The first example of the electrocatalytic multicomponent synthesis of 4-chloro/bromo/iodopyrazoles from hydrazines, acetylacetones and sodium halides under chemical oxidant- and external electrolyte-free conditions has been developed. Sodium halides played a dual role as a halogenation reagent and a supporting electrolyte. Mechanism studies revealed that the bromination reaction proceeded via an ionic pathway, whereas both chlorination and iodination proceeded via a radical pathway.

AQP5 Is a Novel Prognostic Biomarker in Pancreatic Adenocarcinoma.

Background: Pancreatic adenocarcinoma (PAAD) is a highly malignant tumor with a poor prognosis. The identification of effective molecular markers is of great significance for diagnosis and treatment. Aquaporins (AQPs) are a family of water channel proteins that exhibit several properties and play regulatory roles in human carcinogenesis. However, the association between Aquaporin-5 (AQP5) expression and prognosis and tumor-infiltrating lymphocytes in PAAD has not been reported. Methods: AQP5 mRNA expression, methylation, and protein expression data in PAAD were analyzed using GEPIA, UALCAN, HAP, METHSURV, and UCSC databases. AQP5 expression in PAAD patients and cell lines from our cohort was examined using immunohistochemistry and Western blotting. The LinkedOmics database was used to study signaling pathways related to AQP5 expression. TIMER and TISIDB were used to analyze correlations among AQP5, tumor-infiltrating immune cells, and immunomodulators. Survival was analyzed using TCGA and Kaplan-Meier Plotter databases. Results: In this study, we investigated AQP5 expression in PAAD and determined whether the expression of AQP5 is a strong prognostic biomarker for PAAD. We searched and analyzed public cancer databases (GEO, TCGA, HAP, UALCAN, GEPIA, etc.) to conclude that AQP5 expression levels were upregulated in PAAD. Kaplan-Meier curve analysis showed that high AQP5 expression positively correlated with poor prognosis. Using TIMER and TISIDB, we found that the expression of AQP5 was associated with different tumor-infiltrating immune cells, especially macrophages. We found that hypomethylation of the AQP5 promoter region was responsible for its high expression in PAAD. Conclusions: AQP5 can serve as a novel biomarker to predict prognosis and immune infiltration in PAAD.

The Endoplasmic Reticulum-Stressed Head and Neck Squamous Cell Carcinoma Cells Induced Exosomal miR-424-5p Inhibits Angiogenesis and Migration of Humanumbilical Vein Endothelial Cells Through LAMC1-Mediated Wnt/ß-Catenin Signaling Pathway.

Under endoplasmic reticulum (ER) stress, tumor plays multifaceted roles in endothelial cell dysfunction through secreting exosomal miRNAs. However, for the head and neck squamous cell carcinoma (HNSCC), it is still unclear about the impact of ER-stressed HNSCC cell derived exosomes on vascular endothelial cells. To address this gap, herein, systemic research was conducted including isolation and characterization of ER-stressed HNSCC cell (HN4 cell line as an in vitro model) derived exosomes, identification of regulatory exosomal miRNAs, target exploration and downstream signaling pathway investigation of exosomal miRNAs in human umbilical vein endothelial cell (HUVEC). ER-stressed HN4 cell-derived exosomes inhibited angiogenesis and migration of HUVEC cells in vitro. Furthermore, RNA-seq analysis demonstrated that miR-424-5p was highly upregulated in ER-stressed HN4 cell-derived exosomes. Through matrigel tube formation and transwell assays of HUVEC cells, miR-424-5p displayed great capabilities on inhibiting angiogenesis and migration. Finally, based on western blot and luciferase reporter, it was demonstrated that LAMC1 is the target of miR-424-5p which could inhibit the angiogenesis and migration of HUVEC cells by repressing the LAMC1-mediated Wnt/ß-catenin signaling pathway. ER-stressed HNSCC cell-induced exosomal miR-424-5p inhibits angiogenesis and migration of HUVEC cells through LAMC1-mediated Wnt/ß-catenin signaling pathway. This study offers a new insight for understanding the complicated mechanism behind ER-stress induced anti-angiogenesis of HNSCC.

ACE2 and TMPRSS2 in human saliva can adsorb to the oral mucosal epithelium.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is primarily transmitted through droplets. All human tissues with the angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serines 2 (TRMPRSS2) are potential targets of SARS-CoV-2. The role of saliva in SARS-CoV-2 transmission remains obscure. In this study, we attempted to reveal ACE2 and TRMPRSS2 protein expression in human parotid, submandibular, and sublingual glands (three major salivary glands). Then, the binding function of spike protein to ACE2 in three major salivary glands was detected. The expression of ACE2 and TMPRSS2 in human saliva from parotid glands were both examined. Exogenous recombined ACE2 and TMPRSS2 anchoring and fusing to oral mucosal epithelial cells in vitro were also unraveled. ACE2 and TMPRSS2 were found mainly to be expressed in the cytomembrane and cytoplasm of epithelial cells in the serous acinus cells in parotid and submandibular glands. Our research also discovered that the spike protein of SARS-CoV-2 binds to ACE2 in salivary glands in vitro. Furthermore, exogenous ACE2 and TMPRSS2 can anchor and fuse to oral mucosa in vitro. Thus, the expression of ACE2 and TMPRSS2 in human saliva might have implications for SARS-CoV-2 infection.

LINC00536 promotes hepatocellular carcinoma progression via the miR-203b-5p/VEGFA axis.

LncRNAs exert comprehensive effects in regulating the initiation and deterioration of hepatocellular carcinoma (HCC). However, the specific expression profiles and functional mechanisms of LINC00536 in HCC need to be disclosed. The study is intended to clarify the leverage of LINC00536 in HCC and investigate the potential mechanisms for the regulatory role of LINC00536 in the progression of HCC. In our study, LINC00536 was overexpressed in tumor samples of HCC patients and was related to poor prognosis. LINC00536 knockdown impaired cell viability, proliferation, migration, and invasion. LINC00536 can directly bind with miR-203b-5p, trimming the miR-203b-5p expression levels. VEGFA designates as a target of miR-203b-5p. Rescue research indicated that the miR-203b-5p inhibition or VEGFA overexpression could reverse the impaired cell phenotypes induced by LINC00536 knockdown. The in vivo experiments upheld the LINC00536/miR-203b-5p/VEGFA axis in HCC. Conclusively, LINC00536 could promote HCC deterioration via tuning the miR-203b-5p/VEGFA axis. This research may provide theoretical evidence for LINC00536 to get a gratifying therapeutic target for HCC.

Prevalence and Novel Genotypes Identification of Enterocytozoon bieneusi in Dairy Cattle in Yunnan Province, China.

Enterocytozoon bieneusi is a fungus-like protist parasite that can cause diarrhea and enteric diseases. The infection of E. bieneusi has been reported in many host species, including cattle and humans. However, information on prevalence and genotype distribution of E. bieneusi in dairy cattle in Yunnan province in China is still absent. In this study, 490 Holstein Cows and 351 dairy buffalo fecal samples were collected from three regions in Yunnan province, China. By using nest-PCR that targets the internal transcribed spacer (ITS), we found that the prevalence of E. bieneusi was 0.59% (5/841). DNA sequence analysis showed that five E. bieneusi genotypes were identified in this study, including two novel genotypes, YNDCEB-90 and YNDCEB-174, and three known genotypes (I, J, BEB4). Phylogenetic analysis revealed that two novel genotypes, YNDCEB-90 and YNDCEB-174, were clustered into Group 1, representing the zoonotic potential. The remaining genotypes I, J, and BEB4, which are the most frequent genotypes of E. bieneusi infection in cattle and lead to E. bieneusi infection in humans, belonged to Group 2. Although the lower prevalence of E. bieneusi was detected in dairy cattle in Yunnan province, it indicates that dairy cattle should be considered to be one of the potential hosts for transmitting E. bieneusi to humans. These findings are important for the development of effective prevention strategies for microsporidiosis.

FAM83A promotes proliferation and metastasis via Wnt/ß-catenin signaling in head neck squamous cell carcinoma.

This research aimed to investigate the expression and function of FAM83A in the proliferation and metastasis in head and neck squamous cell carcinoma (HNSCC). FAM83A mRNA and protein expressions in HNSCC were detected in primary HNSCC samples and cell lines. The associations between FAM83A expression and clinicopathologic variables were evaluated through tissue microarrays. Besides, FAM83A knockdown and overexpression cell lines were constructed to assess cell growth and metastasis in vitro and the relationship between FAM83A and epithelial-mesenchymal transition (EMT). Furthermore, two models of xenograft tumors in nude mice were used to assess the tumorigenicity and metastasis ability of FAM83A in vivo. In the present study, overexpression of FAM83A in HNSCC samples was significantly associated with tumor size, lymph node status and clinical tumor stages. Mechanically, FAM83A could promote HNSCC cell growth and metastasis by inducing EMT via activating Wnt/ß-catenin signaling pathway. Rescue experiment demonstrated the inhibition of ß-catenin could counteract the function of FAM83A. Also, the FAM83A knockdown could suppress tumor growth and distant metastasis in the xenograft animal models of HNSCC. In conclusion, this study identifies FAM83A as an oncogene of HNSCC. This study provides new insights into the molecular pathways that contribute to EMT in HNSCC. We revealed a previously unknown FAM83A-Wnt-ß-catenin signaling axis involved in the EMT of HNSCC. There may be a potential bi-directional signaling loop between FAM83A and Wnt/ß-catenin signaling pathway in HNSCC.

Lensless phase retrieval based on deep learning used in holographic data storage.

This paper proposes a lensless phase retrieval method based on deep learning (DL) used in holographic data storage. By training an end-to-end convolutional neural network between the phase-encoded data pages and the corresponding near-field diffraction intensity images, the new unknown phase data page can be predicted directly from the intensity image by the network model without any iterations. The DL-based phase retrieval method has a higher storage density, lower bit-error-rate (BER), and higher data transfer rate compared to traditional iterative methods. The retrieval optical system is simple, stable, and robust to environment fluctuations which is suitable for holographic data storage. Besides, we studied and demonstrated that the DL method has a good suppression effect on the dynamic noise of the holographic data storage system.

Tunable band gaps and high carrier mobilities in stanene by small organic molecule adsorption under external electric fields.

The effects of small organic molecule (SOM) adsorption with benzene (C6H6), hexafluorobenzene (C6F6), and p-difluorobenzene (C6H4F2) on the electronic properties of stanene under external electric fields are investigated through first-principles calculations. Different adsorption sites and molecular orientations are considered to determine the most stable configurations of small organic molecule (SOM) adsorption on the surface of stanene. The results show that the internal electric field caused by the adsorption of small organic molecules destroys the symmetry of the two sublattices of stanene in C6H6/stanene, C6F6/stanene and C6H4F2/stanene systems with the most stable configurations, opening the band gaps of stanene with 39.5, 18.9 and 14.5 meV, respectively. Under an external electric field, a wide range of linearly tunable and sizable direct band gaps (31.6-420.1 meV for the C6H6/stanene system, 14.8-587.2 meV for the C6F6/stanene system and 14.5-490.2 meV for the C6H4F2/stanene system) are merely determined by the strength of the composite electric field despite its direction. The mechanism of charge transfer between stanene and organic molecules under an external electric field can be revealed using an equivalent capacitor model to explain the tunable charge transfer. More importantly, the high carrier mobility of the stable SOM/stanene systems under an external electric field is largely retained due to the weak interactions at the interface. These results indicate that the electronic properties of stanene can be effectively modulated by the surface adsorption of organic molecules under an external electric field, providing effective and reversible routes to enhance the performance of stanene for novel electronic devices in the future.

Significant Enhancement of the Polarization Holographic Performance of Photopolymeric Materials by Introducing Graphene Oxide.

Relying on various defects and functional oxygen-containing groups on the basal planes, graphene oxide (GO) is commonly unitized for intimate mixing with a polymer matrix to fabricate high-performance nanocomposite polymeric materials with the characteristics of graphene. Herein, by introducing GO nanosheets in a phenanthraquinone-doped polymethyl methacrylate (PQ/PMMA) photopolymer, we demonstrate that the polarization holographic diffraction efficiency of nanocomposite materials can be dramatically enhanced up to nearly 10 times and the photosensitivity can also be enhanced by more than 3 times. Experimental observations reveal that the incorporation of GO nanosheets serves as a polymerization initiator not only to promote the polymerization of MMA monomers and induce the drafting behavior of the PMMA polymer on its surface but also to effectively modulate the molecular weight of the PQ/PMMA photopolymer by adjusting the doping concentration of GO nanosheets. The current study, for the first time, demonstrates that the modulation of molecular weight for PQ/PMMA photopolymers here exerts a significant impact on their holography performance. In addition, due to the strong physisorption of PQ photosensitizers onto GO nanosheets, the aggregation of PQ around GO-graft-PMMA also facilitates the formation of GO-graft-PMMA/PQ and is beneficial to the enhancement of holographic performance. The emergence of GO-graft-PMMA/PQ nanocomposite materials here is expected to fulfill the requirement of high-performance polarization-sensitive materials in the field of polarization holographic data storage and provide a facile but effective nanocomposite doping strategy to modulate the holographic performance of photopolymers from micro- and mesoscopic levels.