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1.
Angew Chem Int Ed Engl ; : e202415583, 2024 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-39385038

RESUMO

Concurrently achieving high efficiency, mechanical robustness and thermal stability is critical for the commercialization of all-polymer solar cells (APSCs). However, APSCs usually demonstrate complicated morphology, primarily attributed to the polymer chain entanglement which has a detrimental effect on their fill factors (FF) and morphology stability. To address these concerns, an end-group extended polymer acceptor, PY-NFT, was synthesized and studied. The morphology analysis showed a tightly ordered molecular packing mode and a favorable phase separation was formed. The PM6:PY-NFT-based device achieved an exceptional PCE of 19.12% (certified as 18.45%), outperforming the control PM6:PY-FT devices (17.14%). This significant improvement highlights the record-high PCE for binary APSCs. The thermal aging study revealed that the PM6:PY-NFT blend exhibited excellent morphological stability, thereby achieving superior device stability, retaining 90% of initial efficiency after enduring thermal stress (65 °C) for 1500 hours. More importantly, the PM6:PY-NFT blend film exhibited outstanding mechanical ductility with a crack onset strain of 24.1%. Overall, rational chemical structure innovation, especially the conjugation extension strategy to trigger appropriate phase separation and stable morphology, is the key to achieving high efficiency, improved thermal stability and robust mechanical stability of APSCs.

2.
Nanomicro Lett ; 17(1): 37, 2024 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-39397182

RESUMO

Recently published in Joule, Feng Liu and colleagues from Shanghai Jiaotong University reported a record-breaking 20.8% power conversion efficiency in organic solar cells (OSCs) with an interpenetrating fibril network active layer morphology, featuring a bulk p-i-n structure and proper vertical segregation achieved through additive-assisted layer-by-layer deposition. This optimized hierarchical gradient fibrillar morphology and optical management synergistically facilitates exciton diffusion, reduces recombination losses, and enhances light capture capability. This approach not only offers a solution to achieving high-efficiency devices but also demonstrates the potential for commercial applications of OSCs.

3.
Huan Jing Ke Xue ; 45(10): 6112-6128, 2024 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-39455155

RESUMO

In this review, we comprehensively analyzed the distribution of microplastics (MPs) in major water ecosystems in China and the fate of MPs during the water treatment process. The removal efficiency of MPs with different colors, sizes, shapes, and materials was also discussed. The results showed that the abundance of microplastics in the aquatic environment was geographically variable and closely related to human activities. Fibrous and transparent (white) microplastics were the most common features in China's water ecosystems and water treatment plants, with polypropylene (PP), polyethylene (PE), and polystyrene (PS) being the most common polymer types of microplastics. The removal efficiency of MPs varied from different treatment processes significantly. Pre-treatment and primary treatment in wastewater treatment plants (WWTPs) contributed the most to the removal. In the secondary treatment, the sedimentation tank showed more efficiency than the biological treatment processes. Tertiary treatment processes demonstrated remarkable effectiveness in achieving terminal control of MPs, especially membrane technologies. On the contrary, aeration and hydrodynamic effects may have increased the abundance of MPs in WWTPs. In drinking water treatment plants (DWTPs), coagulation-sedimentation processes were found to be the most effective in removing MPs, followed by filtration and disinfection processes. Further, both pre-treatment and post-treatment steps also made significant contributions to MPs removal.


Assuntos
Microplásticos , Poluentes Químicos da Água , Purificação da Água , Microplásticos/isolamento & purificação , Microplásticos/análise , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/análise , Purificação da Água/métodos , China , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Polipropilenos/química
4.
Sci Rep ; 14(1): 24518, 2024 10 18.
Artigo em Inglês | MEDLINE | ID: mdl-39424865

RESUMO

In photoperiod-sensitive plants, the CO-like gene (CONSTANS-like, COL) has a crucial function in regulating the timing of flowering. The blooming period in foxtail millet is greatly influenced by the duration of daylight; however, there is a scarcity of data regarding the molecular properties of the COL genes in the foxtail millet. In this study, we conducted a comprehensive analysis of the COL gene family in foxtail millet at the genome-wide level. We identified 11 SiCOL genes and performed gene structure analysis, which showed pronounced variation in gene length and intron number among the genes. The examination of COL proteins in foxtail millet and other plant species using phylogenetic analysis revealed that they could be clustered into three distinct groups. Cis-element analysis identified elements related to light-responsiveness, hormones, and abiotic stress in the promoter region of the SiCOL gene. Furthermore, tissue-specific expression analysis showed widespread expression of all 11 SiCOL genes in various foxtail millet tissues and organs, particularly in leaves and panicles. Collinearity analysis identified 14 syntenic gene pairs in both foxtail millet and rice. The results also revealed diurnal oscillations in the transcription levels of SiCOL genes under different light conditions. Moreover, among the 11 genes, SiCO, SiCOL1, and SiCOL6 expression levels were negatively correlated with flowering time variation in two foxtail cultivars. Additionally, upon constructing a network of predicted molecular interactions, FLOWER LOCUS-like (FTL) and Phytochromea A (PHY A) were suggested to potentially interact with SiCO, SiCOL1, and SiCOL6. SiCO, SiCOL1, and SiCOL6 have the potential for flowering and heading in foxtail millet. This research enhances our comprehension of the role and control of the SiCOL gene family constituents in foxtail millet, establishing a basis for future investigations.


Assuntos
Flores , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas , Setaria (Planta) , Setaria (Planta)/genética , Setaria (Planta)/crescimento & desenvolvimento , Flores/genética , Flores/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Genoma de Planta , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Fotoperíodo
5.
Sci Rep ; 14(1): 25466, 2024 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-39461994

RESUMO

Gas explosion is one of the five major hazards in mines, with about 36% of such incidents occurring in the excavation working face. Therefore, to investigate the impact of gas explosion propagation laws within excavation roadways, we conducted a simulation analysis of parameters such as peak of explosion overpressure, peak rate of pressure rise, and flame propagation speed in the presence of a Tunnel Boring Machine (TBM). In the presence of the TBM, the explosion overpressure approximately doubles, and the flame propagation speed also greatly increases, exacerbating the explosion hazard. Thus, when investigating gas explosion laws within excavation roadways, the presence of a TBM emerges as a significant factor that cannot be overlooked. Furthermore, an analysis of the effects of methane concentration and gas accumulation length on explosion parameters was conducted. The results indicate that when the flame passes through the TBM baffle, the average flame propagation speed increases the most when the methane concentration is 9.5%, increasing by about 6 times. In addition, as the gas accumulation length increases, both explosion overpressure and flame propagation speed gradually increase. Additionally, TBM has a certain impact on flame propagation and methane dissipation.

6.
BMC Psychol ; 12(1): 555, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39407298

RESUMO

BACKGROUND: The integration of AI in finance has significantly reshaped the role of financial engineers, improving efficiency and decision-making. However, it also affects psychological safety and work-life balance. Financial engineers face increased pressure to keep up with evolving technologies, fear of job displacement due to automation, and blurred boundaries between work and personal life. Exploring the link between AI applications, psychological well-being, and work-life balance is crucial for optimizing individual performance and organizational success, ensuring a sustainable and supportive work environment. OBJECTIVES: This qualitative study investigates how AI-integrated finance applications influence financial engineers' psychological safety and work-life balance. By exploring financial engineers' lived experiences and perceptions, the study seeks to provide insights into the human implications of AI adoption in finance. METHODOLOGY: The study utilized qualitative research methods, specifically thematic analysis, to examine data from 20 informants selected through theoretical sampling. Thematic analysis techniques were employed to identify recurring patterns, themes, and meanings within the data, allowing for a rich exploration of the research questions. FINDINGS: Data analysis revealed several themes related to the impact of AI-integrated applications on financial engineers' psychological safety and work-life balance. These themes include the perception of job security, the role of automation in workload management, and the implications of AI for professional identity and job satisfaction. CONCLUSIONS: This study's findings highlight the multifaceted effects of AI integration in finance, shedding light on the opportunities and challenges it presents for financial engineers. While AI offers potential benefits such as increased efficiency and productivity, it raises concerns about job security and work-related stress. Overall, the study underscores the importance of considering the human implications of AI adoption in finance and calls for proactive measures to support the well-being of financial professionals in an AI-driven environment.


Assuntos
Satisfação no Emprego , Pesquisa Qualitativa , Equilíbrio Trabalho-Vida , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pessoal Administrativo/psicologia , Inteligência Artificial , China , População do Leste Asiático/psicologia , Administração Financeira/métodos , Irã (Geográfico) , Segurança Psicológica , Carga de Trabalho/psicologia , População do Oriente Médio/psicologia
7.
Biomaterials ; 315: 122894, 2024 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-39461061

RESUMO

Prostate cancer (PCa) is associated with poor immunogenicity and lymphocytic infiltration, and immunotherapy effective against PCa remains unavailable. Pyroptosis, a novel immunotherapeutic modality for cancer, promotes systemic immune responses leading to immunogenic cell death in solid tumors. This paper describes the preparation and analysis of PSMAscFv-EVN-GSDMD; this genetically engineered recombinant extracellular vesicle (EV) expresses a single-chain variable antibody fragment (scFv) with high affinity for prostate-specific membrane antigen (PSMA) on their surfaces and is loaded with the N-terminal domain of gasdermin D (GSDMD). Both in vitro and in vivo, PSMAscFv-EVN-GSDMD effectively targeted PSMA-positive PCa cells and induced pyroptosis through the carrier properties of EVs and the specificity of PSMAscFv. In the 22RV1 and PSMA-transfected RM-1-inoculated PCa mouse models, PSMAscFv-EVN-GSDMD efficiently inhibited tumor growth and promoted tumor immune responses. In conclusion, PSMAscFv-EVN-GSDMD can convert the immunosuppressive "cold" tumor microenvironment of PCa into an immunogenic "hot" tumor microenvironment.

8.
Angew Chem Int Ed Engl ; : e202413198, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39221920

RESUMO

Transition metal-catalyzed radical-based enantioconvergent reactions have become a powerful strategy to synthesize enantiopure compounds from racemic starting materials. However, existing methods primarily address precursors with central chirality, neglecting those with axial chirality. Herein, we describe the enantioconvergent reductive coupling of racemic allenes with aldehydes, facilitated by a photoredox, chromium, and cobalt triple catalysis system. This method selectively affords one product from sixteen possible regio- and stereoisomers. The protocol leverages CoIII-H mediated hydrogen atom transfer (MHAT) and Cr-catalyzed radical-polar crossover for efficient stereoablation of axial chirality and asymmetric addition, respectively. Supported by mechanistic insights from control experiments, deuterium labeling, and DFT calculations, our approach offers synthetic chemists a valuable tool for creating enantioenriched chiral homoallylic alcohols, promising to advance radical-based strategies for synthesizing complex chiral molecules.

9.
Adv Healthc Mater ; : e2402916, 2024 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-39344873

RESUMO

Large segmental bone defects often lead to nonunion and dysfunction, posing a significant challenge for clinicians. Inspired by the intrinsic bone defect repair logic of "vascularization and then osteogenesis", this study originally reports a smart implantable hydrogel (PDS-DC) with high mechanical properties, controllable scaffold degradation, and timing drug release that can proactively match different bone healing cycles to efficiently promote bone regeneration. The main scaffold of PDS-DC consists of polyacrylamide, polydopamine, and silk fibroin, which endows it with superior interfacial adhesion, structural toughness, and mechanical stiffness. In particular, the adjustment of scaffold cross-linking agent mixing ratio can effectively regulate the in vivo degradation rate of PDS-DC and intelligently satisfy the requirements of different bone defect healing cycles. Ultimately, PDS hydrogel loaded with free desferrioxamine (DFO) and CaCO3 mineralized ZIF-90 loaded bone morphogenetic protein-2 (BMP-2) to stimulate efficient angiogenesis and osteogenesis. Notably, DFO is released rapidly by free diffusion, whereas BMP-2 is released slowly by pH-dependent layer-by-layer disintegration, resulting in a significant difference in release time, thus matching the intrinsic logic of bone defect repair. In vivo and in vitro results confirm that PDS-DC can effectively realize high-quality bone generation and intelligently regulate to adapt to different demands of bone defects.

10.
Rev Esp Enferm Dig ; 2024 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-39297610

RESUMO

A 48-year-old woman presented to the outpatient clinic with a 4-month history of alternating diarrhea and constipation with bloating. Physical examination revealed a body mass index of 22.89 kg/m², normal development, and no tenderness or rebound tenderness in the abdomen. The patient has maintained a stable body size since birth, with a previously healthy status and no history of abdominal surgery or trauma. Endoscopic examination revealed an abnormal channel between the posterior wall of the duodenal bulb to the hepatic flexure of the colon. The patient was managed with conservative treatment, including acid suppression and modulation of the gut microbiota, and was closely monitored. Surgical intervention would only be considered in the event of severe symptoms or complications. Over a five-month follow-up period, the patient's symptoms improved.

11.
Eur Radiol ; 2024 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-39285029

RESUMO

OBJECTIVES: To differentiate cerebral microbleeds (CMBs) and calcifications using quantitative susceptibility mapping (QSM). METHODS: CMBs were visualized and located using QSM from susceptibility-weighted imaging data collected on a 3-T MR scanner. Calcifications of the pineal gland and the choroid plexus were localized first using CT. All calcifications and CMBs were assessed using QSM to evaluate their magnetic susceptibility. The distribution of the magnetic susceptibility for the CMBs was determined and the CT attenuation was correlated with the mean magnetic susceptibility for the calcifications. RESULTS: A total of 232 hypointense foci were selected from the QSM data: 121 were CMBs and 111 were calcifications. The mean magnetic susceptibility was -214 ± 112 ppb for the calcifications and 392 ± 204 ppb for the CMBs. The minimum value of magnetic susceptibility was 75 ppb for all the CMBs and the maximum value was -52 ppb for all the calcifications. The calcifications were clearly differentiable from the CMBs from the sign alone (p < 0.001). The magnetic susceptibility for the CMBs was 299 ± 133 ppb in the lobar subcortical white matter and 499 ± 220 ppb for deep CMBs in the basal ganglia, thalamus, and brainstem. There was a significant difference in the susceptibility between these two regions (p < 0.001). CONCLUSION: The sign of the magnetic susceptibility was sufficient to differentiate calcifications and CMBs. The concentration of calcium or iron can be determined from the susceptibility value itself. The deep CMBs had higher susceptibility on average than lobar bleeds. CLINICAL RELEVANCE STATEMENT: This study's ability to differentiate between CMBs and calcifications using QSM could enhance diagnostic accuracy, guiding more precise treatment decisions for stroke or tumor patients. KEY POINTS: The sign of magnetic susceptibility is sufficient to differentiate calcifications and CMBs. QSM can successfully differentiate calcifications from microbleeds. The concentration of calcium or iron can be determined from the susceptibility value itself.

12.
Hypertens Res ; 47(10): 2811-2825, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39117946

RESUMO

Recent evidence suggests that necroptosis may contribute to the development of kidney injury. Renalase is a novel secretory protein that exerts potent prosurvival and anti-inflammatory effects. We hypothesized that renalase could protect the kidney from salt-induced injury by modulating necroptosis. High salt and renalase treatments were administered to Dahl salt-sensitive (SS) rats, renalase knockout (KO) mice, and HK-2 cells. Furthermore, a cohort of 514 eligible participants was utilized to investigate the association between single nucleotide polymorphisms (SNPs) in the genes RIPK1, RIPK3, and MLKL, and the risk of subclinical renal damage (SRD) over 14 years. A high-salt diet significantly increased the expression of key components of necroptosis, namely RIPK1, RIPK3, and MLKL, as well as the release of inflammatory factors in SS rats. Treatment with recombinant renalase reduced both necroptosis and inflammation. In renalase KO mice, salt-induced kidney injury was more severe than in wild-type mice, but supplementation with renalase attenuated the kidney injury. In vitro experiments with HK-2 cells revealed high salt increased necroptosis and inflammation. Renalase exhibited a dose-dependent decrease in salt-induced necroptosis, and this cytoprotective effect was negated by the knockdown of PMCA4b, which is the receptor of renalase. Furthermore, the cohort study showed that SNP rs3736724 in RIPK1 and rs11640974 in MLKL were significantly associated with the risk of SRD over 14 years. Our analysis shows that necroptosis plays a significant role in the development of salt-induced kidney injury and that renalase confers its cytoprotective effects by inhibiting necroptosis and inflammation.


Assuntos
Inflamação , Rim , Camundongos Knockout , Necroptose , Proteínas Quinases , Ratos Endogâmicos Dahl , Proteína Serina-Treonina Quinases de Interação com Receptores , Animais , Necroptose/efeitos dos fármacos , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Inflamação/patologia , Masculino , Humanos , Ratos , Rim/patologia , Rim/efeitos dos fármacos , Camundongos , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Cloreto de Sódio na Dieta , Polimorfismo de Nucleotídeo Único , Linhagem Celular
13.
Anal Chim Acta ; 1322: 343066, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-39182988

RESUMO

For hepatocellular carcinoma (HCC), N-glycosylation has been proved to be widely involved in various aspects of the disease, including development, metastasis, subtyping, diagnosis and prognosis. The common practice is to discover biomarkers in situ of cancer occurrence (i.e., cancer vs. adjacent tissues) yet to clinically monitor in sera because of non-invasiveness. This study benchmarks N-glycoproteomics characterization of common differential tissue and serum N-glycoproteins of patients with HCC. Differential N-glycosylation in matched tissue and serum samples from the same patients were quantitatively characterized at the intact N-glycopeptide molecular level, and 29 common N-glycoproteins were found. Subcellular localization analysis was carried out to confirm the tissue originality. Secreted N-glycoprotein APOH was up-regulated, and transmembrane and intracellular N-glycoproteins including OSMR, GAT2, CSF-1 and MAGI3 were down-regulated.


Assuntos
Carcinoma Hepatocelular , Glicoproteínas , Neoplasias Hepáticas , Proteômica , Humanos , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/metabolismo , Glicoproteínas/sangue , Glicoproteínas/metabolismo , Biomarcadores Tumorais/sangue , Glicosilação , Masculino , Pessoa de Meia-Idade , Feminino , Benchmarking
14.
Nanoscale Horiz ; 9(10): 1792-1803, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-39135517

RESUMO

Metamaterials have demonstrated significant potential for enhancing nonlinear processes at the nanoscale. The presence of narrowband hot-spots and highly inhomogeneous mode-field distributions often limit the enhancement of nonlinear interactions over larger spatial scales. This has posed a formidable challenge in achieving simultaneous enhancement across a broadband spectral range, significantly constraining the potential of photonic nanostructures in enhancing nonlinear frequency conversion. Here, we propose a broadband resonant mode matching method through near-field examinations that supports the multipole modes and enables the development of an ultrabroadband-enhanced 3-5 µm mid-infrared frequency upconversion technique utilizing a hyperbolic triangular pyramidal metasurface. The gap-plasma mode of the hyperbolic metamaterial multilayer system excites narrowly high-order resonances at near-infrared pump light wavelengths, while the slow-light effect generated by the dipoles achieves ultrabroadband near-field enhancement at mid-infrared wavelengths. The symmetry breaking of the triangular structure localizes these resonant modes at the tips, enabling mode-matched modulation at different wavelengths, and thus boosting the nonlinear frequency conversion process. Our approach provides a promising platform for metasurface-based frequency conversion techniques.

16.
Sensors (Basel) ; 24(13)2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-39001167

RESUMO

In the field of wireless strain monitoring, it is difficult for the traditional metal-made antenna sensor to conform well with steel structures and monitor large strain deformation. To solve this problem, this study proposes a flexible antenna strain sensor based on a ductile graphene film, which features a 6.7% elongation at break and flexibility due to the microscopic wrinkle structure and layered stacking structure of the graphene film. Because of the use of eccentric embedding in the feeding form, the sensor can be miniaturized and can simultaneously monitor strain in two directions. The sensing mechanism of the antenna is analyzed using a void model, and an antenna is designed based on operating frequencies of 3 GHz and 3.5 GHz. The embedding size is optimized using a Smith chart and impedance matching principle. Both the simulation and experimental results verify that the resonant frequency and strain magnitude are linearly inversely proportional. The experimental results show that the strain sensitivity is 1.752 kHz/µÎµ along the geometric length and 1.780 kHz/µÎµ along the width, with correlation coefficients of 0.99173 and 0.99295, respectively.

18.
Dalton Trans ; 53(29): 12370-12380, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38993174

RESUMO

The residue of antibiotics and various pollutants has led to an urgent issue in environmental pollution control. In this study, we constructed an S-scheme P-TiO2@Zn-MOF heterojunction by self-assembling phosphonate-based MOFs on mesoporous phosphate-TiO2 beads. Compared to monomers, the P-TiO2@Zn-MOF2.0 heterojunction exhibits significantly higher photocatalytic activity for the photo-oxidative degradation of ciprofloxacin (97.2% in 60 min) and tetracyclic (TC) (94.5% in 100 min) and the photo-reduction of Cr(VI) (92.7% in 60 min) under simulated sunlight. Experimental results and calculations revealed the effective separation and transfer of photogenerated carriers at the P-TiO2@Zn-MOF2.0 S-scheme heterojunction interface, enabling the formation of highly active superoxide and hydroxyl radicals. Furthermore, the hybrid maintained excellent Cr(VI) photoreduction performance after recycling tests in actual electroplating industry wastewater at a strongly acidic pH.

19.
World J Clin Cases ; 12(19): 3752-3759, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38994321

RESUMO

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) is a common mental and behavioral disorder among children. AIM: To explore the focus of attention deficit hyperactivity disorder parents and the effectiveness of early clinical screening. METHODS: This study found that the main directions of parents seeking medical help were short attention time for children under 7 years old (16.6%) and poor academic performance for children over 7 years old (12.1%). We employed a two-stage experiment to diagnose ADHD. Among the 5683 children evaluated from 2018 to 2021, 360 met the DSM-5 criteria. Those diagnosed with ADHD underwent assessments for letter, number, and figure attention. Following the exclusion of ADHD-H diagnoses, the detection rate rose to 96.0%, with 310 out of 323 cases identified. RESULTS: This study yielded insights into the primary concerns of parents regarding their children's symptoms and validated the efficacy of a straightforward diagnostic test, offering valuable guidance for directing ADHD treatment, facilitating early detection, and enabling timely intervention. Our research delved into the predominant worries of parents across various age groups. Furthermore, we showcased the precision of the simple exclusion experiment in discerning between ADHD-I and ADHD-C in children. CONCLUSION: Our study will help diagnose and guide future treatment directions for ADHD.

20.
Angew Chem Int Ed Engl ; : e202412977, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39079914

RESUMO

Perylene diimides (PDIs) have garnered considerable attention due to its immense potential in photocatalysis. However, manipulating the molecular packing within their aggregates and enhancing the efficiency of photogenerated carrier recombination remain significant challenges. In this study, we demonstrate the incorporation of a PDI unit into a covalent organic framework (COF), named PDI-PDA, by linking an ortho-substituted PDI with p-phenylenediamine (PDA) to control its intermolecular aggregation. The incorporation enables precise modulation of electron transfer dynamics, leading to a ten-fold increase in the efficiency of photocatalytic oxidation of thioether to sulfoxide with PDI-PDA compared to the PDI molecular counterpart, achieving yields exceeding 90%. Electron property studies and density functional theory calculations show that the PDI-PDA with its well-defined crystal structure, enhances π-π stacking and lowers the electron transition barrier. Moreover, the strong electron-withdrawing ability of the PDI unit promotes the spatial separation of the valency band maximum and conduction band minimum of PDI-PDA suppressing the rapid recombination of photogenerated electron-hole pairs and improving charge separation efficiency to give high photocatalytic efficiency. This study provides a brief yet effective way for the improvement of the photocatalytic efficiency of commonly used PDI-based dyes by integrating them into a framework skeleton.

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