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1.
Chem Sci ; 15(24): 9112-9119, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38903225

RESUMO

The weak spin-orbit coupling (SOC) in metal-free organic molecules poses a challenge in achieving phosphorescence emission. To attain pure phosphorescence in RTP organic emitters, a promising molecular design concept has been proposed. This involves incorporating n → π* transitions and leveraging the heavy atomic effect within the spin-orbit charge transfer-induced intersystem crossing (SOCT-ISC) mechanism of bipolar molecules. Following this design concept, two bipolar metal-free organic molecules (PhSeB and PhSeDB) with donor-acceptor (D-A) and acceptor-donor-acceptor (A-D-A) configurations have been synthesized. When the molecular configuration changes from D-A to A-D-A, PhSeDB exhibits stronger electron coupling and n → π* transitions, which can further enhance the spin-orbit coupling (SOC) together with the heave atom effect from the selenium atom. By the advanced synergism among enhanced n → π* transitions, heavy atom effect and magnified electron coupling to efficiently promote phosphorescence emission, PhSeDB can achieve pure RTP emission in both the solution and doped solid film. Thanks to the higher spin-orbit coupling matrix elements (SOCMEs) for T1 ↔ S0, PhSeDB attains the highest phosphorescence quantum yield (ca. 0.78) among all the RTP organic emitters reported. Consequently, the purely organic phosphorescent light-emitting diodes (POPLEDs) based on PhSeDB achieve the highest external quantum efficiencies of 18.2% and luminance of 3000 cd m-2. These encouraging results underscore the significant potential of this innovative molecular design concept for highly efficient POPLEDs.

2.
J Phys Chem Lett ; 15(23): 6174-6182, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38836596

RESUMO

Electrides have emerged as promising materials with exotic properties due to the presence of localized electrons detached from all atoms. Despite the continuous discovery of many new electrides, most of them are based on atypical compositions, and their applications require an inert surface structure to passivate reactive excess electrons. Here, we demonstrate a different route to attain tunable electrides. We first report that monolayer transition metal dichalcogenides (TMDCs) exhibit weak electride characteristics, which is the remainder of the electride feature of the transition metal sublattice. By introducing chalcogen vacancies, the enhanced electride characteristics are comparable to those of known electrides. Since the precise tailoring of the chalcogen vacancy concentration has been achieved experimentally, we proposed that TMDCs can be used to build electrides with controllable intensities. Furthermore, we demonstrate that the electride states at the chalcogen vacancy of monolayer TMDCs will play an important role in catalyzing hydrogen evolution reactions.

3.
Fundam Res ; 4(3): 550-556, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38933186

RESUMO

The discovery of covalent H3S and clathrate structure LaH10 with excellent superconducting critical temperatures at high pressures has facilitated a multitude of research on compressed hydrides. However, their superconducting pressures are too high (generally above 150 GPa), thereby hindering their application. In addition, making room-temperature superconductivity close to ambient pressure in hydrogen-based superconductors is challenging. In this work, we calculated the chemically "pre-compressed" Be-H by heavy metals Th and Ce to stabilize the superconducting phase near ambient pressure. An unprecedented ThBeH8 (CeBeH8) with a "fluorite-type" structure was predicted to be thermodynamically stable above 69 GPa (76 GPa), yielding a T c of 113 K (28 K) decompressed to 7 GPa (13 GPa) by solving the anisotropic Migdal-Eliashberg equations. Be-H vibrations play a vital role in electron-phonon coupling and structural stability of these ternary hydrides. Our results will guide further experiments toward synthesizing ternary hydride superconductors at mild pressures.

4.
Chem Sci ; 15(22): 8506-8513, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38846396

RESUMO

The modulation of emission color is one of the most critical topics in the research field of organic light-emitting diodes (OLEDs). Currently, only two ways are commonly used to tune the emission colors of OLEDs: one is to painstakingly synthesize different emitters with diverse molecular structures, the other is to precisely control the degree of aggregation or doping concentration of one emitter. To develop a simpler and less costly method, herein we demonstrate a new strategy in which the emission colors of OLEDs can be continuously changed with UV light during the device fabrication process. The proof of concept is established by a chromene-based Ir(iii) complex, which shows bright green emission and yellow emission before and after UV irradiation, respectively. Consequently, under different durations of UV irradiation, the resulting Ir(iii) complex is successfully used as the emitter to gradually tune the emission colors of related solution-processed OLEDs from green to yellow. Furthermore, the electroluminescent efficiencies of these devices are unaffected or even increased during this process. Therefore, this work demonstrates a distinctive point of view and approach for modulating the emission colors of OLEDs, which may prove great inspiration for the fabrication of multi-colored OLEDs with only one emitter.

5.
Nucleic Acids Res ; 52(D1): D1380-D1392, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37889076

RESUMO

DNA methylation plays a crucial role in tumorigenesis and tumor progression, sparking substantial interest in the clinical applications of cancer DNA methylation biomarkers. Cancer-related whole-genome bisulfite sequencing (WGBS) data offers a promising approach to precisely identify these biomarkers with differentially methylated regions (DMRs). However, currently there is no dedicated resource for cancer DNA methylation biomarkers with WGBS data. Here, we developed a comprehensive cancer DNA methylation biomarker database (MethMarkerDB, https://methmarkerdb.hzau.edu.cn/), which integrated 658 WGBS datasets, incorporating 724 curated DNA methylation biomarker genes from 1425 PubMed published articles. Based on WGBS data, we documented 5.4 million DMRs from 13 common types of cancer as candidate DNA methylation biomarkers. We provided search and annotation functions for these DMRs with different resources, such as enhancers and SNPs, and developed diagnostic and prognostic models for further biomarker evaluation. With the database, we not only identified known DNA methylation biomarkers, but also identified 781 hypermethylated and 5245 hypomethylated pan-cancer DMRs, corresponding to 693 and 2172 genes, respectively. These novel potential pan-cancer DNA methylation biomarkers hold significant clinical translational value. We hope that MethMarkerDB will help identify novel cancer DNA methylation biomarkers and propel the clinical application of these biomarkers.


Assuntos
Biomarcadores Tumorais , Carcinogênese , Metilação de DNA , Bases de Dados Genéticas , Humanos , Biomarcadores Tumorais/genética , Metilação de DNA/genética , Sequenciamento Completo do Genoma , Carcinogênese/genética , Elementos Facilitadores Genéticos
6.
J Phys Chem Lett ; 14(43): 9698-9704, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37875810

RESUMO

Borophene has attracted much interest due to its rich configurations and novel properties such as Dirac fermions and superconductivity. The recently emerged bilayer borophene mitigates the oxidation problem when exposed to air, yet most studies ignore the influence of charge transfer induced by metal substrates on structural stability. Here we identified 31 monolayer borophene polymorphs that are stabilized on Au(111), Ag(111), or Cu(111) substrates through first-principle calculations. Interestingly, two novel semiconducting bilayer borophene polymorphs with band gaps of 0.37 and 0.42 eV were screened by integrating these monolayers. The formation of interlayer bonding contributed by the delocalized electrons is responsible for the semiconductivity. The predicted highest electron mobility reaches 2.01 × 104 cm2V-1 s-1, implying the possibility as a semiconductor device with a low power consumption. Moreover, light was also systemically thrown on the factors that may affect the electronic properties of bilayer borophenes and the positional preference of interlayer bonds.

7.
EBioMedicine ; 97: 104846, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37879219

RESUMO

BACKGROUND: Cervical squamous cell carcinoma (CSCC) and adenocarcinoma (CAde) are two major pathological types of cervical cancer (CC), but their high-resolution heterogeneity of tumor and immune microenvironment remains elusive. METHODS: Here, we performed single-nucleus RNA sequencing (snRNA-seq) from five CSCC and three CAde samples, and systematically outlined their specific transcriptome atlas. FINDINGS: We found CD8+ T cells in CSCC were more cytotoxic but lower exhausted compared to those in CAde, and phagocytic MRC1+ macrophages were specifically enriched in CSCC. Interestingly, we discovered that pro-tumoral cancer-associated myofibroblasts (myoCAFs) and cancer-associated vascular-fibroblasts (vCAFs) were more abundant in CSCC, and further verified their pro-metastatic roles in vitro. Furthermore, we also identified some specific chemotherapy drugs for CSCC (Dasatinib and Doramapimod) and CAde (Pyrimethamine and Lapatinib) by revealing their heterogeneity in transcriptomic profiles of malignant epithelial cells, and further verified their specific sensitivity in cell lines and constructed CC-derived organoids. Cell-cell communication networks revealed that the pathways of NRG1-ERBB2, and FN1-ITAG3 were specific for CAde and CSCC, respectively, which may partly explain the specificities of identified chemotherapy drugs. INTERPRETATION: Our study described the immune heterogeneity and specific cellular interactions between CSCC and CAde, which could provide insights for uncovering pathogenesis and designing personalized treatment. FUNDINGS: National Key R&D Program of China (2021YFC2701201), National Natural Science Foundation of China (82072895, 82141106, 82103134, 81903114).


Assuntos
Adenocarcinoma , Carcinoma de Células Escamosas , Neoplasias do Colo do Útero , Feminino , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Análise de Sequência de RNA , Microambiente Tumoral/genética
8.
Angew Chem Int Ed Engl ; 62(41): e202309739, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37626014

RESUMO

Highly efficient near-infrared (NIR) emitters have significant applications in medical and optoelectronic fields, but the development stays a great challenge due to the energy gap law. Here, we report two NIR phosphorescent Ir(III) complexes which display emission peaks around 730 nm with a narrow full width at half maximum of only 43 nm. Therefore, pure NIR luminescence can be obtained without having a very long emission wavelength, thus alleviating the restriction of the energy gap law, and obtaining impressively high photoluminescence quantum yield up to 0.70. More importantly, the pure NIR organic light-emitting diode (OLED) fabricated by the solution-processed mothed shows outstanding device performance with the highest external quantum efficiency of 16.43 %, which sets a new record for solution-processed NIR-OLEDs based on different emitters. This work sheds light on the development of Ir(III) complexes with narrowband emissions as highly efficient pure NIR-emitters.

9.
BMC Nurs ; 22(1): 259, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37550733

RESUMO

BACKGROUND: The benefits of home-based cardiac rehabilitation exercise are well-established and depend on long-term adherence. However, there is no uniform and recognized cardiac rehabilitation criterion to assess home-based cardiac rehabilitation exercise adherence for patients with cardiovascular disease. This study aimed to develop a home-based cardiac rehabilitation exercise adherence scale and to validate its psychometric properties among patients with chronic heart failure. METHODS: The dimensions and items of the scale were created based on grounded theory research, literature content analysis, and defined by a Delphi survey. Item analysis was completed to assess the discrimination and homogeneity of the scale. Factor analysis was adopted to explore and validate the underlying factor structure of the scale. Content validity and calibration validity were evaluated using the Delphi survey and correlation analysis, respectively. Reliability was evaluated by Cronbach's α coefficients, split-half reliability coefficients, and test-retest reliability coefficients. RESULTS: A scale covering four dimensions and 20 items was developed for evaluating home-based cardiac rehabilitation exercise adherence. The content validity index of the scale was 0.986. In exploratory factor analysis, a four-factor structure model was confirmed, explaining 75.1% of the total variation. In confirmatory factor analysis, the four-factor structure was supported by the appropriate fitting indexes. Calibration validity of the scale was 0.726. In terms of reliability, the Cronbach's α coefficient of the scale was 0.894, and the Cronbach's α coefficients of dimensions ranged from 0.848 to 0.914. The split-half reliability coefficient of the scale was 0.695. The test-retest reliability coefficient of the scale was 0.745. CONCLUSION: In this study, a home-based cardiac rehabilitation exercise adherence scale was developed and its appropriate psychometric properties were confirmed.

10.
Dalton Trans ; 52(26): 8927-8942, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37337994

RESUMO

A series of four-coordinated PtII(C^N)(N-donor ligand)Cl-type complexes have been synthesized through a combination of long-size C^N-type and N-donor ligands. In addition, by varying the coordinating site in the N-donor ligand, a distorted molecular configuration has been constructed in these complexes. Their photophysical features, aggregation-induced phosphorescence emission (AIPE) behaviors, electrochemical properties and electroluminescence (EL) performance have been investigated in detail. It has been found that their AIE behaviors can be enhanced by both employing long-size ligands, especially the N-donor ligand, and adopting a distorted molecular configuration, furnishing a high AIE factor (αAIE) of ca. 13.8. Critically, benefitting from their long-size C^N-type and N-donor ligands, these PtII(C^N)(N-donor ligand)Cl-type complexes can exhibit very sensitive AIE behaviors in a mixture of THF-H2O, indicated by their noticeable emission increase with a low H2O volumetric fraction (fw) of ca. 0.1 in their THF solution. In solution-processed organic light-emitting diodes (OLEDs), they can achieve a luminance of 6743 cd m-2 at 13.5 V, a maximum external quantum efficiency (ηext) of 13.8%, a maximum current efficiency (ηL) of 42.4 cd A-1 and a maximum power efficiency (ηP) of 34.4 lm W-1, respectively. Hence, this research can provide key information for developing phosphorescent complexes with a highly sensitive AIE response and impressive EL ability.

11.
Health Qual Life Outcomes ; 21(1): 56, 2023 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-37280621

RESUMO

BACKGROUND: It is significant for the healthy outcome of patients with psoriasis (PSO) to improve their self-management efficacy. A standardized assessment tool, however, was lacking. Therefore, we aimed to develop a self-management efficacy questionnaire for patients with PSO (SMEQ-PSO) and evaluate its psychometric properties. METHODS: A cross-sectional study developing clinical evaluation tool was conducted from October 2021 to August 2022. In the process of developing SMEQ-PSO, three phases were involved: item generation, item evaluation, and psychometric evaluation. RESULTS: The SMEQ-PSO with five dimensions and 28 items was developed. The questionnaire's content validity index was 0.976. Exploratory factor analysis indicated a five-factor structure (self-efficacy of psychosocial adaptation, self-efficacy of daily life management, self-efficacy of skin management, self-efficacy of disease knowledge management and self-efficacy of disease treatment management) that explained 62.039% of the total variance. Confirmatory factor analysis indicated appropriate fit of the five-factor model. The overall Cronbach'α coefficient was 0.930, the test-retest reliability was 0.768 and the split half reliability coefficients was 0.952. CONCLUSIONS: The 28-item SMEQ-PSO is a reliable and valid tool that can be used to assess the self-management efficacy among patients with PSO and provide personalized interventions based on their individual circumstances to improve their health outcomes.


Assuntos
Psoríase , Autogestão , Humanos , Autoeficácia , Psicometria/métodos , Reprodutibilidade dos Testes , Estudos Transversais , Qualidade de Vida , Psoríase/terapia , Psoríase/psicologia , Inquéritos e Questionários
12.
Patient Prefer Adherence ; 17: 851-860, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36999162

RESUMO

Purpose: This study aimed to explore a conceptual model of home-based cardiac rehabilitation exercise adherence and reveal its internal behavioral logic. Patients and Methods: A constructivist grounded theory design was adopted to explore the conceptual model of home-based cardiac rehabilitation exercise adherence. Semi-structured interviews were completed to collect qualitative data for constructing the conceptual model. The theoretical saturation and validation strategies were adopted to demonstrate the adequacy of qualitative data. A three-level coding procedure with constant comparisons was completed to analyze this qualitative data. Results: A total of 21 patients with chronic heart failure were recruited in this study. As a result of this study, 32 initial codes, 12 category codes, and four core categories were extracted, namely, seeking supports, rehabilitation exercise, exercise monitoring and information feedback. According to the internal behavioral logic, the conceptual model of home cardiac rehabilitation exercise adherence was finally formed. In this closed-chain model, seeking supports is the initial adherence behavior, and rehabilitation exercise is the core adherence behavior, and exercise monitoring is the key adherence behavior, and information feedback is the driving adherence behavior. Conclusion: The conceptual model of home-based cardiac rehabilitation exercise adherence in patients with chronic heart failure was developed, revealing its internal behavioral logic and providing theoretical references for developing relevant clinical research tools with comprehensive coverage and identifying weak links.

13.
Proc Natl Acad Sci U S A ; 120(8): e2218405120, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36787368

RESUMO

Most metals adopt simple structures such as body-centered cubic (BCC), face-centered cubic (FCC), and hexagonal close-packed (HCP) structures in specific groupings across the periodic table, and many undergo transitions to surprisingly complex structures on compression, not expected from conventional free-electron-based theories of metals. First-principles calculations have been able to reproduce many observed structures and transitions, but a unified, predictive theory that underlies this behavior is not yet in hand. Discovered by analyzing the electronic properties of metals in various lattices over a broad range of sizes and geometries, a remarkably simple theory shows that the stability of metal structures is governed by electrons occupying local interstitial orbitals and their strong chemical interactions. The theory provides a basis for understanding and predicting structures in solid compounds and alloys over a broad range of conditions.

14.
Support Care Cancer ; 30(12): 10043-10050, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36350381

RESUMO

BACKGROUND: Serum lipid management is an important health management goal for breast cancer patients with endocrine therapy, and serum lipid knowledge is a substantial factor influencing patients' serum lipid management behavior. The aim of this study was to explore the relationship between family support, serum lipid knowledge and quality of life in breast cancer women with endocrine therapy. METHODS: Through convenience sampling, 301 women who had been treated in the First Affiliated Hospital of China Medical University and Liaoning Cancer Hospital were selected to fill in the questionnaire of knowledge-attitude-practice (KAP) on serum lipids, family support questionnaire (FSQ), and the functional assessment of cancer therapy-breast cancer (FACT-B). Pearson correlation coefficient was used to analyze the correlation between the three. Multiple linear regression model was used to analyze the influencing factors of quality of life in breast cancer patients with endocrine therapy. RESULTS: The average score of KAP on serum lipids was 42.62 ± 7.333, the average score of family support was 12.55 ± 2.390, and the average score of quality of life was 97.13 ± 21.347, all above the medium level. Family support of breast cancer women with endocrine therapy was positively correlated with serum lipid knowledge and quality of life. Disease stage, family support, and serum lipid knowledge were the influencing factors of quality of life of breast cancer women with endocrine therapy. CONCLUSION: Good family support is associated with better serum lipid knowledge in breast cancer women with endocrine therapy. Therefore, interventions that aim to improve the level of family support may be one way to improve the knowledge level of serum lipid, prevent cardiovascular and cerebrovascular diseases, and improve the quality of life.


Assuntos
Neoplasias da Mama , Qualidade de Vida , Humanos , Feminino , Inquéritos e Questionários , Quimioterapia Adjuvante/efeitos adversos , Lipídeos/uso terapêutico
15.
Biomedicines ; 10(9)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36140208

RESUMO

Annulus fibrosus (AF) damage is proven to prompt intervertebral disc (IVD) degeneration, and unrepaired AF lesions after surgical discectomy may boost herniation of the nucleus pulposus (NP) which may lead to further compression of neural structures. Moreover, vascular and neural ingrowth may occur within the defect which is known as a possible reason for discogenic pain. Due to a limited healing capacity, an effective strategy to repair and close the AF defect is necessary. In this study, using electrospinning technology, two nature polymers, silk fibroin and gelatin, were linked to imitate the unique lamellae structure of native AF. Our findings revealed that a multilayer electrospun-aligned fibroin/gelatin scaffold with mechanical and morphological properties mimicking those of native AF lamellae have been developed. The average diameter of the nanofiber is 162.9 ± 38.8 nm. The young's modulus is around 6.70 MPa with an ultimate tensile strength of around 1.81 MP along preferred orientation. The in vitro test confirmed its biocompatibility and ability to maintain cell viability and colonization. Using a porcine model, we demonstrated that the multilayer-aligned scaffold offered a crucial microenvironment to induce collagen fibrous tissue production within native AF defect. In the implant-repaired AF, H&E staining showed homogeneous fibroblast-like cell infiltration at the repaired defect with very little vascular ingrowth, which was confirmed by magnetic resonance imaging findings. Picrosirius red staining and immunohistochemical staining against type I collagen revealed positively stained fibrous tissue in an aligned pattern within the implant-integrated site. Relative to the intact control group, the disc height index of the serial X-ray decreased significantly in both the injury control and implant group at 4 weeks and 8 weeks (p < 0.05) which indicated this scaffold may not reverse the degenerative process. However, the results of the discography showed that the effectiveness of annulus repair of the implant group is much superior to that of the untreated group. The scaffold, composed with nature fibroin/gelatin polymers, could potentially enhance AF healing that could prevent IVD recurrent herniation, as well as neural and neovascular ingrowth after discectomy surgeries.

16.
Phys Chem Chem Phys ; 24(27): 16884-16890, 2022 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-35789236

RESUMO

Clathrates are inclusion compounds featured with host framework cages and trapped guest atoms or small molecules. Recently, the first boron-carbon (B-C) clathrate SrB3C3 was successfully synthesized at high pressures near 50 GPa. Upon the substitution of guest atoms, clathrates exhibit tunable applications. For example, LaB3C3 possesses an indirect band gap of near 1.3 eV, whereas the ScB3C3 clathrate is ferroelectric with an above-room-temperature Curie temperature of ∼370 K. To the best of our knowledge, however, there is no report on the investigation of B-C framework clathrates with non-equivalent B : C ratios. By using first-principles swarm-intelligence structure searching computations, we identified two metastable I4/mmm SrB2C4 and LaB4C2 clathrates at 50 GPa, and the framework cage contains six quadrilaterals and eight hexagons with a trapped guest metal located at the center. Their dynamic and enthalpy stabilities may be retained at ambient pressure. Moreover, the possible clathrates are extended by the substitution of the guest atoms with other metals in groups 2, 3, and 4, showing a tunable superconducting critical temperature (Tc) and considerable Vickers hardness (Hv). Intriguingly, a metal-to-semiconductor transition occurs in MB2C4 as the atomic number order of alkaline earth metals increases (M: Mg → Ca → Sr → Ba). The estimated Tc value for I4/mmm SrB4C2 is 19.2 K, while SrB2C4 and BaB2C4 are evaluated as superhard materials with Hv values of 43.6 and 41.2 GPa under ambient conditions, respectively.

17.
Adv Mater ; 34(13): e2106204, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35040527

RESUMO

Coordination nanosheets are an emerging class of 2D, bottom-up materials having fully π-conjugated, planar, graphite-like structures with high electrical conductivities. Since their discovery, great effort has been devoted to expand the variety of coordination nanosheets; however, in most cases, their low crystallinity in thick films hampers practical device applications. In this study, mixtures of nickel and copper ions are employed to fabricate benzenehexathiolato (BHT)-based coordination nanosheet films, and serendipitously, it is found that this heterometallicity preferentially forms a structural phase with improved film crystallinity. Spectroscopic and scattering measurements provide evidence for a bilayer structure with in-plane periodic arrangement of copper and nickel ions with the NiCu2 BHT formula. Compared with homometallic films, heterometallic films exhibit more crystalline microstructures with larger and more oriented grains, achieving higher electrical conductivities reaching metallic behaviors. Low dependency of Seebeck coefficient on the mixing ratio of nickel and copper ions supports that the large variation in the conductivity data is not caused by change in the intrinsic properties of the films. The findings open new pathways to improve crystallinity and to tune functional properties of 2D coordination nanosheets.

18.
J Phys Chem Lett ; 13(1): 190-197, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34967221

RESUMO

Photocatalytic water splitting is a promising method that uses sunlight to generate hydrogen from water to provide clean and renewable energy resources. Two-dimensional materials with abundant active sites are ideal candidates for achieving this goal; however, few of the known ones can meet the rigorous requirement of photocatalytic water splitting. By using first-principles swarm-intelligence search calculations, we have successfully identified two new semiconducting SiCP2 and SiCP4 monolayers. Their band-edge heights evidently straddle the redox potentials of water. For the more prominent SiCP4 monolayer, additional external biases of 0.32 V for water oxidation and 0.03 V for the hydrogen reduction half-reaction would be enough to drive its reaction sequences at pH 0, and it can spontaneously proceed to the water oxidation half-reaction in a neutral solution. Interestingly, the excellent optical absorbance ability (∼104 cm-1) and high carrier mobility (∼105 cm2 V-1 s-1) of SiCP2 and SiCP4 facilitate the utilization of sunlight and the fast transportation of photogenerated carriers. All of these properties make SiCP2 and SiCP4 monolayers promising candidates for applications in photocatalytic water splitting.

20.
ACS Appl Mater Interfaces ; 13(30): 36020-36032, 2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34283914

RESUMO

The various applications of dinuclear complexes have attracted increasing attention. However, the electroluminescence efficiencies of dinuclear Pt(II) complexes are far from satisfactory. Herein, based on the triphenylamine core, we develop four dinuclear Pt(II) complexes that cover the emission colors from yellow to red with high photoluminescence quantum efficiencies of up to 0.79 in doped films. The solid-state structure of PyDPt is revealed by the single-crystal X-ray diffraction investigation. Besides, solution-processed OLEDs have been fabricated with different electron transport materials. With higher electron mobility and excellent hole-blocking ability, 1,3,5-tri(m-pyridin-3-ylphenyl)benzene (TmPyPB) can help to realize good charge balance in related OLEDs. In addition, angle-dependent PL spectra reveal the preferentially horizontal orientation of these dinuclear Pt(II) complexes in doped CBP films, which benefits the outcoupling efficiencies. Therefore, the yellow OLED based on PyDPt shows unexpected high performance with a peak current efficiency of up to 78.7 cd/A and an external quantum efficiency of up to 22.4%, which is the highest EQE reported for OLEDs based on dinuclear Pt(II) complexes so far. This study demonstrates the great potential of developing dinuclear Pt(II) complexes for achieving excellent electroluminescence efficiencies.

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