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1.
Acc Chem Res ; 57(8): 1111-1122, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38372967

ABSTRACT

ConspectusMolecular polyhedral cages, notable for their enclosed inner cavities, can possess varying degrees of symmetry, spanning from regular Platonic polyhedra to lower symmetry forms that may display chirality. Crafting chiral molecular cages typically involves using building blocks containing stereogenic elements or arranging achiral components in a manner that lacks mirror and inversion symmetries. Achieving precise control over their chirality poses both significance and challenges.In this Account, we present an overview of our research endeavors in the realm of chiral molecular polyhedral cages, drawing inspiration from Buckminster Fuller's "Face-Rotating Polyhedra (FRP)". Mathematically, FRP introduce a unique form of chirality distinguished by a rotating pattern around the center of each face, setting it apart from regular polyhedra.Molecular FRP can be constructed using two types of facial building blocks. The first includes rigid, planar molecules such as truxene and triazatruxene, which exhibit either clockwise or counterclockwise rotations in two dimensions. The second category involves propeller-like molecules, e.g., tetraphenylethylene, 1,2,3,4,5-penta(4-phenylaldehyde)pyrrole, and tridurylborane, displaying dynamic stereochemistry.The synthesis of FRP may potentially yield a diverse array of stereoisomers. Achieving high stereoselectivity becomes feasible through the selection of building blocks with specific substitution patterns and rigidity. Prominent noncovalent repulsive forces within the resulting cages often play a pivotal role in the dynamic covalent assembly process, ultimately leading to the formation of thermodynamically stable FRP products.The capacity to generate a multitude of stereoisomers, combined with the integration of chiral vertices, has facilitated investigations into phenomena such as chiral self-sorting and the "sergeant and soldiers" chiral amplification effect in FRP. Even the inclusion of one chiral vertex significantly impacts the stereochemical configuration of the entire cage. While many facial building blocks establish a stable rotational pattern in FRP, other units, such as tridurylborane, can dynamically transition between P and M configurations within the cage structures. The kinetic characteristics of such stereolabile FRP can be elucidated through physicochemical investigations.Our research extends beyond the FRP concept to encompass mathematical analysis of these structures. Graph theory, particularly the coloring problem, sheds light on the intricate facial patterns exhibited by various FRP stereoisomers and serves as an efficient tool to facilitate the discovery of novel FRP structures. This approach offers a fresh paradigm for designing and analyzing chiral molecular polyhedral cages, showcasing in our work the synergy between mathematics and molecular design.

2.
BMC Complement Med Ther ; 24(1): 21, 2024 Jan 04.
Article in English | MEDLINE | ID: mdl-38178115

ABSTRACT

BACKGROUND: This study aims to assess the efficacy and safety of Qingpeng ointment (QPO), a Tibetan medicine for alleviating symptoms in individuals with acute gouty arthritis (AGA). METHODS: This study was a randomized, double-blind, placebo-controlled trial that involved individuals with AGA whose joint pain, as measured on a visual analog scale (VAS) from 0 to 10, was equal to or greater than 3. The participants were randomly assigned to either the QPO or the placebo group and received their respective treatments twice daily for seven consecutive days. In case of intolerable pain, the participants were allowed to use diclofenac sodium sustained-release tablets as a rescue medicine. The primary outcomes measured were joint pain and swelling, while the secondary outcomes included joint mobility, redness, serum uric acid levels, C-reactive protein levels, and the amount of remaining rescue medicine. Any adverse events that occurred during the trial were also recorded. RESULTS: A total of 203 cases were divided into two groups, with balanced baselines: 102 in the QPO group and 101 in the placebo group. For joint pain, differences between the groups were notable in the VAS scores [1.75 (0, 3.00) versus 2.00 (1.00, 3.50); P = 0.038], changes in VAS [5.00 (3.00, 6.00) versus 4.00 (2.00, 6.00); P = 0.036], and disappearance rate [26.47% compared to 15.84%; P = 0.046] after treatment. Concerning joint swelling, significant between-group differences were observed in the VAS scores [1.00 (0, 2.30) versus 2.00 (0.70, 3.00); P = 0.032] and disappearance rate [33.33% compared to 21.78%; P = 0.046] at treatment completion. The QPO group exhibited a statistically significant mobility improvement compared to the placebo group (P = 0.004). No significant differences were found in other secondary outcomes. Five patients, four from the QPO group and one from the other, encountered mild adverse events, primarily skin irritation. All of these cases were resolved after dosage reduction or discontinuation of the medication. CONCLUSIONS: Compared to the placebo, QPO exhibits positive effects on AGA by alleviating pain, reducing swelling, and enhancing joint mobility, without causing significant adverse effects. TRIAL REGISTRATION: ISRCTN34355813. Registered on 25/01/2021.


Subject(s)
Arthritis, Gouty , Humans , Arthritis, Gouty/drug therapy , Ointments/therapeutic use , Medicine, Tibetan Traditional/adverse effects , Uric Acid , Pain/drug therapy , Arthralgia
3.
Medicine (Baltimore) ; 102(47): e36144, 2023 Nov 24.
Article in English | MEDLINE | ID: mdl-38013284

ABSTRACT

This study aimed to explore the mode of action of Yiqiyangyinquyu prescription (YP) against Sjögren's syndrome (SS) by combining network pharmacology with molecular docking techniques. YP's active components and target proteins were identified using the BATMAN-traditional Chinese medicine database. Concurrently, targets associated with SS were extracted from databases, including Genecards, Online Mendelian Inheritance in Man, and Therapeutic Target Database. The standard targets were then imported into the STRING database to construct a protein-protein interaction network. We then conducted gene ontology and Kyoto encyclopedia of genes and genomes enrichment analyses, which were succeeded by molecular docking studies to validate core active components and key targets. Finally, in vitro experiments and molecular dynamics simulation were conducted to substantiate the therapeutic efficacy of YP in treating SS. A total of 206 intersection targets and 46 active compounds were identified. Gene ontology analysis unveiled that YP targets were primarily enriched in cellular responses to chemical stress, inflammation, and cell proliferation. Key enriched signaling pathways encompassed the interleukin 17, hypoxia-inducible factor-1, tumor necrosis factor (TNF-α), and advanced glycation end products-receptor for AGEs (AGE-RAGE) signaling pathways. Molecular docking results demonstrated high-affinity between neotanshinone C, tanshiquinone B, miltionone I, TNF-α, interleukin 1 beta (IL-1ß), and interleukin 6 (IL-6). Noteworthy, TNF-α, considered the most important gene in YP against SS, binds to YP most stably, which was further validated by molecular dynamics simulation. In vitro experiments confirmed YP's capacity to reduce TNF-α, IL-1ß, and IL-6 expression, effectively alleviating SS-related inflammation. YP demonstrated a significant anti-inflammatory effect by suppressing inflammatory cytokines (TNF-α, IL-6, and IL-1ß), providing experimental evidence for its clinical application in treating SS.


Subject(s)
Drugs, Chinese Herbal , Sialadenitis , Sjogren's Syndrome , Humans , Sjogren's Syndrome/drug therapy , Tumor Necrosis Factor-alpha , Interleukin-6 , Molecular Docking Simulation , Network Pharmacology , Inflammation/drug therapy , Databases, Genetic , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use
4.
Int J Rheum Dis ; 26(11): 2223-2232, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37740638

ABSTRACT

AIM: Sjögren syndrome (SS) is a slowly progressive, inflammatory, autoimmune disease. The aim of this study was to construct the DNA methylation profiles of whole blood of SS patients and healthy controls (HC), and to explore the role of differentially methylated genes in the pathogenesis of the disease. METHODS: Whole-genome bisulfite sequencing was performed on three SS patients and four HC. The biological function of genes associated with differentially methylated regions (DMRs) was investigated using Gene Ontology functional analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis, using network-based key driver analysis (KDA) to find KDA genes. In clinical samples of SS patients and controls, the expression levels of KDA genes were validated by quantitative real-time polymerase chain reaction and immunohistochemical analysis. Moreover, the diagnostic value of KDA genes for SS was confirmed using receiver operating characteristic curves. RESULTS: We identified 322 DMRs, annotated as 162 associated genes. Six genes were selected via the number of networks of KDA genes. Differential expression of genes such as human leukocyte antigen (HLA) class I, ADAR, and OAS2 was observed in patients' peripheral blood mononuclear cells and the minor salivary glands, which can be used as potential diagnostic biomarkers for SS. CONCLUSION: Clinical sample validation suggested that HLA class I, ADAR, and OAS2 might play a role in the development of SS. Our study shows epigenetic regulatory mechanisms and potential disease markers associated with SS, which in turn will enable us to identify new therapeutic targets.


Subject(s)
DNA Methylation , Sjogren's Syndrome , Humans , Sjogren's Syndrome/diagnosis , Sjogren's Syndrome/genetics , Leukocytes, Mononuclear , Epigenesis, Genetic , Biomarkers
5.
Angew Chem Int Ed Engl ; 62(4): e202215367, 2023 Jan 23.
Article in English | MEDLINE | ID: mdl-36428269

ABSTRACT

Chiral nanographenes with both high fluorescence quantum yields (ΦF ) and large dissymmetry factors (glum ) are essential to the development of circularly polarized luminescence (CPL) materials. However, most studies have been focused on the improvement of glum , whereas how to design highly emissive chiral nanographenes is still unclear. In this work, we propose a new design strategy to achieve chiral nanographenes with high ΦF by helical π-extension of strongly luminescent chromophores while maintaining the frontier molecular orbital (FMO) distribution pattern. Chiral nanographene with perylene as the core and two dibenzo[6]helicene fragments as the wings has been synthesized, which exhibits a record high ΦF of 93 % among the reported chiral nanographenes and excellent CPL brightness (BCPL ) of 32 M-1 cm-1 .

6.
Chinese Journal of School Health ; (12): 299-301, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-964447

ABSTRACT

Objective@#To understand the infectious disease prevention and control among primary and secondary schools in Hebei Province from 2019 to 2021 and to provide a scientific basis for promoting epidemic prevention and control in schools.@*Methods@#Relevant indicators of infectious disease prevention and control in primary and secondary schools were collected and screened from the on site supervision and inspection data uploaded from various places, and analyzed with SPSS 22.0 software.@*Results@#The qualified rates of infectious disease prevention and control in primary and secondary schools in Hebei Province from 2019 to 2021 were 77.11%, 89.74% and 96.24%, respectively, the difference was statistically significant( χ 2=455.45, P <0.01). The qualified rates of infectious disease prevention and control in primary schools, middle schools and high schools from 2019 to 2021 increased by year, the difference was statistically significant( χ 2=319.49, 118.74, 25.73, P <0.05). The qualified rates of six infectious disease prevention and control indicators such as morning inspection record, special person responsible for epidemic report, registration record of absence due to illness increased by year, the difference was statistically significant( χ 2=140.34, 9.10, 113.55 , 163.71 , 286.74, 329.18, P <0.05).@*Conclusion@#Steady improvement in school infectious disease prevention and control has been observed, while qualification rate in primary school and rural area still need to be improved, with missing or late report. Government support and talent policy, hardware and sofeware construction, as management level should be strengthened.

7.
Trials ; 23(1): 387, 2022 May 12.
Article in English | MEDLINE | ID: mdl-35549757

ABSTRACT

BACKGROUND: Acute gouty arthritis (AGA) is an inflammatory arthritis clinically characterized by severe pain, swelling, and restricted movement of joints, which may cause physical disability and decrease quality of life. The use of recommended first-line treatment agents for AGA may be limited by adverse events. There has been a traditional use of alternative therapies for AGA. Tibetan medicine Qingpeng ointment is one of the on-market herbal products used for symptom relief of AGA. Previous clinical studies indicated that Qingpeng ointment can relieve pain, swelling, redness, and dysfunction of joints in patients with AGA. However, there is no rigorous randomized trial to demonstrate its benefit for AGA. In order to evaluate the efficacy and safety of Qingpeng ointment for AGA, we designed a randomized controlled trial. METHODS: This study is designed as a multi-center, randomized, double-blind, placebo-controlled trial. Two hundred and six adults with acute flare of gout, and visual analogue scale (VAS) score of joint pain ≥ 3 points will be recruited. Participants will be randomly assigned to herbal treatment or placebo group at a ratio of 1:1. Qingpeng ointment, or equal placebo ointment, will be applied topically at involved joints twice a day for consecutive 7 days. Patients in both groups would be allowed giving diclofenac sodium sustained-release tablets as rescue therapy when VAS score of joint pain ≥ 7 points during the treatment. The primary outcomes will be joint pain measured by VAS score, and joint swelling measured using width and thickness of affected joints and VAS score. Other outcome measures will be joint mobility, joint redness, C-reactive protein, serum uric acid, and the use of rescue medicine as well as adverse effect. DISCUSSION: To the best of our knowledge, this study is the first multi-center, randomized, double-blind, and placebo-controlled clinical trial to assess the efficacy of Tibetan medicine Qingpeng ointment for AGA. The findings of this study would provide evidence for its use to relieve symptoms of AGA. TRIAL REGISTRATION: ISRCTN ISRCTN34355813 . Registered on 25 January 2021.


Subject(s)
Arthritis, Gouty , Drugs, Chinese Herbal , Adult , Arthralgia/drug therapy , Arthritis, Gouty/chemically induced , Arthritis, Gouty/diagnosis , Arthritis, Gouty/drug therapy , Double-Blind Method , Drugs, Chinese Herbal/adverse effects , Edema , Humans , Medicine, Tibetan Traditional , Multicenter Studies as Topic , Ointments/therapeutic use , Pain/drug therapy , Quality of Life , Randomized Controlled Trials as Topic , Treatment Outcome , Uric Acid
8.
Article in English | MEDLINE | ID: mdl-35463097

ABSTRACT

Traditional Chinese medicine (TCM) has been used successfully to treat rheumatoid arthritis (RA). QingreHuoxue treatment (QingreHuoxue decoction [QRHXD]/QingreHuoxue external preparation [QRHXEP]) is a Chinese medicine treatment for RA. To date, very few studies have compared the long-term effects of QRHXD with those of conventional disease-modifying antirheumatic drugs on RA disease activity and radiological progression. QRHXD delayed the radiological progression and showed long-term clinical efficacy of RA. In clinical experiments, the clinical evidence of delaying the radiological progression of RA patients was obtained. A portion of the patients who participated in the "Traditional Chinese Medicine QingreHuoxue Treatment vs. the Combination of Methotrexate and Hydroxychloroquine for Active Rheumatoid Arthritis" study were followed up for 52 weeks, and intention-to-treat (ITT) and compliance protocol (PP) analyses were used to collect and compare the clinical indicators and imaging data between baseline and week 52. Two radiologists who were blind to treatment scored the images independently. Of the 468 subjects, 141 completed the 52-week follow-up. There were no significant differences among the three groups: the traditional Chinese medicine comprehensive treatment group, the Western medicine treatment group, and the integrated traditional Chinese and Western medicine treatment group. There were no differences in the total Sharp score, joint space stenosis score, and joint erosion score at baseline or 52 weeks. In the comparison of the estimated annual radiographic progression (EARP) and the actual annual Sharp total score changes among the three groups, the actual changes were much lower than the EARP at baseline. The radiological progress in all three groups was well controlled. Results of the ITT and PP data sets showed that the disease activity score 28 level of the three groups at 52 weeks was significantly lower than that at baseline. During the 52-week treatment period, the clearance of heat and promotion of blood circulation controlled disease activity and delayed the radiological progress of active RA.

9.
J Am Chem Soc ; 143(43): 17958-17963, 2021 Nov 03.
Article in English | MEDLINE | ID: mdl-34665638

ABSTRACT

The development of helicene molecules with significant chiroptical responses covering a broad range of the visible spectrum is highly desirable for chiral optoelectronic applications; however, their absorption dissymmetry factors (gabs) have been mostly lower than 0.01. In this work, we report unprecedented B,N-embedded double hetero[7]helicenes with nonbonded B and N atoms, which exhibit excellent chiroptical properties, such as strong chiroptical activities from 300 to 700 nm, record high gabs up to 0.033 in the visible spectral range, and tunable circularly polarized luminescence (CPL) from red to near-infrared regions (600-800 nm) with high photoluminescence quantum yields (PLQYs) up to 100%. As revealed by theoretical analyses, the high gabs values are related to the separate molecular orbital distributions owing to the incorporation of nonbonded B and N atoms. The new type of B,N-embedded double heterohelicenes opens up an appealing avenue to the future exploitation of high-performance chiroptical materials.

10.
Front Pharmacol ; 12: 679588, 2021.
Article in English | MEDLINE | ID: mdl-34113254

ABSTRACT

Traditional Chinese medicine (TCM) has been used successfully to treat rheumatoid arthritis (RA). Qingre Huoxue treatment (Qingre Huoxue decoction (QRHXD)/Qingre Huoxue external preparation (QRHXEP)) is a therapeutic scheme of TCM for RA. To date, there have been few studies comparing the efficacy and safety of QRHXD and conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) for the treatment of active RA. This was investigated in a multicenter, double-blind, randomized controlled trial involving 468 Chinese patients with active RA [disease activity score (DAS)-28 > 3.2] treated with QRHXD/QRHXEP (TCM group), methotrexate plus hydroxychloroquine [Western medicine (WM) group], or both [integrative medicine (IM) group]. Patients were followed up for 24 weeks. The primary outcome measure was the change in DAS-28 from baseline to 24 weeks. The secondary outcome measures were treatment response rate according to American College of Rheumatology 20, 50, and 70% improvement criteria (ACR-20/50/70) and the rate of treatment-related adverse events (TRAEs). The trial was registered at ClinicalTrials.gov (NCT02551575). DAS-28 decreased in all three groups after treatment (p < 0.0001); the score was lowest in the TCM group (p < 0.05), while no difference was observed between the WM and IM groups (p > 0.05). At week 24, ACR-20 response was 73.04% with TCM, 80.17% with WM, and 73.95% with IM (based on the full analysis set [FAS], p > 0.05); ACR-50 responses were 40.87, 47.93, and 51.26%, respectively, (FAS, p > 0.05); and ACR-70 responses were 20.87, 22.31, and 25.21%, respectively, (FAS, p > 0.05). Thus, treatment efficacy was similar across groups based on ACR criteria. On the other hand, the rate of TRAEs was significantly lower in the TCM group compared to the other groups (p < 0.05). Thus, QRHXD/QRHXEP was effective in alleviating the symptoms of active RA-albeit to a lesser degree than csDMARDs-with fewer side effects. Importantly, combination with QRHXD enhanced the efficacy of csDMARDs. These results provide evidence that QRHXD can be used as an adjunct to csDMARDs for the management of RA, especially in patients who experience TRAEs with standard drugs. Clinical Trial Registration: ClinicalTrials.gov, identifier NCTNCT025515.

11.
Chem Commun (Camb) ; 57(45): 5566-5569, 2021 Jun 07.
Article in English | MEDLINE | ID: mdl-33969857

ABSTRACT

An X-shaped double [7]heterohelicene 1 bearing four thiadiazole units is synthesized by regioselective cyclodehydrogenation. Enantiopure 1 exhibits excellent chiroptical properties with an impressive absorption dissymmetry factor of up to 0.027, as well as a compact π-stacked homochiral assembly which is unprecedented in the realm of double helicenes.

12.
Light Sci Appl ; 10(1): 85, 2021 Apr 19.
Article in English | MEDLINE | ID: mdl-33875636

ABSTRACT

Interfacial host-guest complexation offers a versatile way to functionalize nanomaterials. However, the complicated interfacial environment and trace amounts of components present at the interface make the study of interfacial complexation very difficult. Herein, taking the advantages of near-single-molecule level sensitivity and molecular fingerprint of surface-enhanced Raman spectroscopy (SERS), we reveal that a cooperative effect between cucurbit[7]uril (CB[7]) and methyl viologen (MV2+2I-) in aggregating Au NPs originates from the cooperative adsorption of halide counter anions I-, MV2+, and CB[7] on Au NPs surface. Moreover, similar SERS peak shifts in the control experiments using CB[n]s but with smaller cavity sizes suggested the occurrence of the same guest complexations among CB[5], CB[6], and CB[7] with MV2+. Hence, an unconventional exclusive complexation model is proposed between CB[7] and MV2+ on the surface of Au NPs, distinct from the well-known 1:1 inclusion complexation model in aqueous solutions. In summary, new insights into the fundamental understanding of host-guest interactions at nanostructured interfaces were obtained by SERS, which might be useful for applications related to host-guest chemistry in engineered nanomaterials.

13.
Chemistry ; 27(29): 7882-7886, 2021 May 20.
Article in English | MEDLINE | ID: mdl-33780575

ABSTRACT

A series of photoswitchable cyclopentadienone derivative dimers bearing bromo, thienyl, 4-(dimethylamino)phenyl, 3-pyridinyl, 4-nitrophenyl and cyano groups was designed and facilely synthesized. Photoswitching properties such as the photoconversions in the photostationary state (PSS), the thermal kinetics and thermal half-lives of photoisomers were systematically investigated. These photoswitches show high fatigue resistance and large photoconversions in the PSS. This work proves that the photoswitching properties of photoswitches based on cyclopentadienone dimers can be tuned by substitution groups and also pave the way to functionalize the cyclopentadienone derivative dimer-based photoswitch, which is important for its future applications.

14.
Nat Commun ; 11(1): 1678, 2020 Mar 31.
Article in English | MEDLINE | ID: mdl-32235828

ABSTRACT

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

15.
ACS Omega ; 5(3): 1305-1311, 2020 Jan 28.
Article in English | MEDLINE | ID: mdl-32010799

ABSTRACT

Currently, ternary CuCo2S4 sulfides are intensively investigated as electrode materials for electrochemical capacitors due to their low cost, high conductivity, and synergistic effect. The research of CuCo2S4 materials for energy storage has gradually grown from 2016. The supercapacitive performances of CuCo2S4 electrodes for electrochemical capacitors are briefly reviewed in this work. The structure, morphology, and particle size of CuCo2S4 are related to the synthesis conditions and electrochemical performances. The thin films of CuCo2S4 nanostructures deposited on conductive substrates and their composites both show better properties than single CuCo2S4. CuCo2S4 and its composites reveal large potential for asymmetric capacitors, delivering high energy densities. However, there is still much new space remaining for future research. The possible development directions, challenges, and opportunities for CuCo2S4 materials are also discussed.

16.
Nat Commun ; 10(1): 5480, 2019 12 02.
Article in English | MEDLINE | ID: mdl-31792204

ABSTRACT

Covalently linked π-stacked dimers represent the most significant platform for elucidating the relationship between molecular alignments and their properties. Here, we present the one-pot synthesis of two intramolecularly π-stacked dimers and disclose how intramolecular stacking modes dictate photoswitching properties. The dimer, which features cofacially stacked chromophores and geometrically favours intramolecular photochemical [2 + 2] cycloadditions, displays a nearly irreversible photoswitching behaviour. By contrast, the dimer, bearing crosswise stacked chromophores, is geometrically unfavourable for the cycloaddition and exhibits a highly reversible photoswitching process, in which the homolysis and reformation of carbon-carbon single bonds are involved. Moreover, the chiral carbon centres of both dimers endow these photoswitches with chirality and the separated enantiomers exhibit tuneable chiroptical properties by photoswitching. This work reveals that intramolecular stacking modes significantly influence the photochemical properties of π-stacked dimers and offers a design strategy toward chiral photoswitchable materials.

17.
Nanomaterials (Basel) ; 9(10)2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31581488

ABSTRACT

Hierarchical composite films grown on current collectors are popularly reported to be directly used as electrodes for supercapacitors. Highly dense and conductive NiCo2O4 nanowires are ideal backbones to support guest materials. In this work, low crystalline MnO2 nanoflakes are electrodeposited onto the surface of NiCo2O4 nanowire films pre-coated on nickel foam. Each building block in the composite films is a NiCo2O4-MnO2 core-shell nanowire on conductive nickel foam. Due to the co-presence of MnO2 and NiCo2O4, the MnO2@NiCo2O4@Ni electrode exhibits higher specific capacitance and larger working voltage than the NiCo2O4@Ni electrode. It can have a high specific capacitance of 1186 F·g-1 at 1 A·g-1. When the core-shell NiCo2O4-MnO2 composite and activated carbon are assembled as a hybrid capacitor, it has the highest energy density of 29.6 Wh·kg-1 at a power density of 425 W·kg-1 with an operating voltage of 1.7 V. This work shows readers an easy method to synthesize composite films for energy storage.

18.
J Am Chem Soc ; 141(32): 12797-12803, 2019 Aug 14.
Article in English | MEDLINE | ID: mdl-31330100

ABSTRACT

A π-extended double [7]carbohelicene 2 with fused pyrene units was synthesized, revealing considerable intra- and intermolecular π-π interactions as confirmed with X-ray crystallography. As compared to the previous double [7]carbohelicene 1, the π-extended homologue 2 demonstrated considerably red-shifted absorption with an onset at 645 nm (1: 550 nm) corresponding to a smaller optical gap of 1.90 eV (1: 2.25 eV). A broad near-infrared emission from 600 to 900 nm with a large Stokes shift of ∼100 nm (2.3 × 103 cm-1) was recorded for 2, implying formation of an intramolecular excimer upon excitation, which was corroborated with femtosecond transient absorption spectroscopy. Moreover, 2 revealed remarkable chiral stability with a fairly high isomerization barrier of 46 kcal mol-1, according to density functional theory calculations, which allowed optical resolution by chiral HPLC and suggests potential applications in chiroptical devices.

19.
Chemistry ; 25(5): 1293-1299, 2019 Jan 24.
Article in English | MEDLINE | ID: mdl-30334293

ABSTRACT

Triindolo-truxene, a C3 -symmetric molecule with a large π-conjugated plane, has six methylene carbon atoms and three aromatic carbon atoms that can be facilely functionalized. Herein, butyl, carbonyl, cyano, and/or malononitrile groups were introduced at six methylene carbon atoms (6-, 14-, 22- or 8-, 16-, 24-positions) and/or three aromatic carbon atoms (2-, 10-, and 18-positions) of triindolo-truxene to produce eight derivatives. Their photophysical properties, electrochemical properties, and molecular assembly can be effectively modulated by substituents and substitution patterns. Incorporation of electron-deficient groups led to redshifts in both the absorption and emission of these derivatives and also lowered their HOMO and LUMO levels. Different substitution patterns resulted in the different intramolecular donor-acceptor interactions. Electron-deficient substituents at the methylene carbon atoms in the 6-, 14-, and 22-positions led to intramolecular charge transfer from the fluorene arms to the truxene core, whereas the corresponding substitutions at the methylene carbon atoms in the 8-, 16-, and 24-positions resulted in intramolecular charge transfer from the truxene core to the fluorene arms. The molecular packing in single crystals and molecular aggregation in solution are also influenced by the substituents and substitution patterns. This work provides a straightforward strategy to alter the properties of triindolo-truxene.

20.
Nanomaterials (Basel) ; 8(10)2018 Sep 20.
Article in English | MEDLINE | ID: mdl-30241330

ABSTRACT

The research on supercapacitors has been attractive due to their large power density, fast charge/discharge speed and long lifespan. The electrode materials for supercapacitors are thus intensively investigated to improve the electrochemical performances. Various transition metal layered double hydroxides (LDHs) with a hydrotalcite-like structure have been developed to be promising electrode materials. Earth-abundant metal hydroxides are very suitable electrode materials due to the low cost and high specific capacity. This is a review paper on NiMn LDHs for supercapacitor application. We focus particularly on the recent published papers using NiMn LDHs as electrode materials for supercapacitors. The preparation methods for NiMn LDHs are introduced first. Then, the structural design and chemical modification of NiMn LDH materials, as well as the composites and films derived from NiMn LDHs are discussed. These approaches are proven to be effective to enhance the performance of supercapacitor. Finally, the reports related to NiMn LDH-based asymmetric supercapacitors are summarized. A brief discussion of the future development of NiMn LDHs is also provided.

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