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1.
Small ; 20(16): e2306989, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38032164

RESUMO

Hybrid organic-inorganic perovskite (HOIP) ferroelectric materials have great potential for developing self-powered electronic transducers owing to their impressive piezoelectric performance, structural tunability and low processing temperatures. Nevertheless, their inherent brittle and low elastic moduli limit their application in electromechanical conversion. Integration of HOIP ferroelectrics and soft polymers is a promising solution. In this work, a hybrid organic-inorganic rare-earth double perovskite ferroelectric, [RM3HQ]2RbPr(NO3)6 (RM3HQ = (R)-N-methyl-3-hydroxylquinuclidinium) is presented, which possesses multiaxial nature, ferroelasticity and satisfactory piezoelectric properties, including piezoelectric charge coefficient (d33) of 102.3 pC N-1 and piezoelectric voltage coefficient (g33) of 680 × 10-3 V m N-1. The piezoelectric generators (PEG) based on composite films of [RM3HQ]2RbPr(NO3)6@polyurethane (PU) can generate an open-circuit voltage (Voc) of 30 V and short-circuit current (Isc) of 18 µA, representing one of the state-of-the-art PEGs to date. This work has promoted the exploration of new HOIP ferroelectrics and their development of applications in electromechanical conversion devices.

2.
J Exp Bot ; 75(7): 1903-1918, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-37856192

RESUMO

The plant cuticle is an important protective barrier on the plant surface, constructed mainly by polymerized cutin matrix and a complex wax mixture. Although the pathway of plant cuticle biosynthesis has been clarified, knowledge of the transcriptional regulation network underlying fruit cuticle formation remains limited. In the present work, we discovered that tomato fruits of the NAC transcription factor SlNOR-like1 knockout mutants (nor-like1) produced by CRISPR/Cas9 [clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9] displayed reduced cutin deposition and cuticle thickness, with a microcracking phenotype, while wax accumulation was promoted. Further research revealed that SlNOR-like1 promotes cutin deposition by binding to the promoters of glycerol-3-phosphate acyltransferase6 (SlGPAT6; a key gene for cutin monomer formation) and CUTIN DEFICIENT2 (SlCD2; a positive regulator of cutin production) to activate their expression. Meanwhile, SlNOR-like1 inhibits wax accumulation, acting as a transcriptional repressor by targeting wax biosynthesis, and transport-related genes 3-ketoacyl-CoA synthase1 (SlKCS1), ECERIFERUM 1-2 (SlCER1-2), SlWAX2, and glycosylphosphatidylinositol-anchored lipid transfer protein 1-like (SlLTPG1-like). In conclusion, SlNOR-like1 executes a dual regulatory effect on tomato fruit cuticle development. Our results provide a new model for the transcriptional regulation of fruit cuticle formation.


Assuntos
Solanum lycopersicum , Fatores de Transcrição , Fatores de Transcrição/metabolismo , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Fenótipo , Ceras/metabolismo
3.
Angew Chem Int Ed Engl ; 63(2): e202313590, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-37814153

RESUMO

The ability to generate and manipulate photoluminescence (PL) behavior has been of primary importance for applications in information security. Excavating novel optical effects to create more possibilities for information encoding has become a continuous challenge. Herein, we present an unprecedented PL temporary quenching that highly couples with thermodynamic phase transition in a hybrid crystal (DMML)2 MnBr4 (DMML=N,N-dimethylmorpholinium). Such unusual PL behavior originates from the anomalous variation of [MnBr4 ]2- tetrahedrons that leads to non-radiation recombination near the phase transition temperature of 340 K. Remarkably, the suitable detectable temperature, narrow response window, high sensitivity, and good cyclability of this PL temporary quenching will endow encryption applications with high concealment, operational flexibility, durability, and commercial popularization. Profited from these attributes, a fire-new optical encryption model is devised to demonstrate high confidential information security. This unprecedented optical effect would provide new insights and paradigms for the development of luminescent materials to enlighten future information encryption.

4.
Angew Chem Int Ed Engl ; 63(14): e202319650, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38275283

RESUMO

Luminescent ferroelectrics are holding exciting prospect for integrated photoelectronic devices due to potential light-polarization interactions at electron scale. Integrating ferroelectricity and long-lived afterglow emission in a single material would offer new possibilities for fundamental research and applications, however, related reports have been a blank to date. For the first time, we here achieved the combination of notable ferroelectricity and afterglow emission in an organic-inorganic hybrid material. Remarkably, the presented (4-methylpiperidium)CdCl3 also shows noticeable antiferroelectric behavior. The implementation of cationic customization and halogen engineering not only enables a dramatic enhancement of Curie temperature of 114.4 K but also brings a record longest emission lifetime up to 117.11 ms under ambient conditions, realizing a leapfrog improvement of at least two orders of magnitude compared to reported hybrid ferroelectrics so far. This finding would herald the emergence of novel application potential, such as multi-level density data storage or multifunctional sensors, towards the future integrated optoelectronic devices with multitasking capabilities.

5.
Plant J ; 112(4): 982-997, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36164829

RESUMO

Chloroplasts play a crucial role in plant growth and fruit quality. However, the molecular mechanisms of chloroplast development are still poorly understood in fruits. In this study, we investigated the role of the transcription factor SlBEL2 (BEL1-LIKE HOMEODOMAIN 2) in fruit of Solanum lycopersicum (tomato). Phenotypic analysis of SlBEL2 overexpression (OE-SlBEL2) and SlBEL2 knockout (KO-SlBEL2) plants revealed that SlBEL2 has the function of inhibiting green shoulder formation in tomato fruits by affecting the development of fruit chloroplasts. Transcriptome profiling revealed that the expression of chloroplast-related genes such as SlGLK2 and SlLHCB1 changed significantly in the fruit of OE-SlBEL2 and KO-SlBEL2 plants. Further analysis showed that SlBEL2 could not only bind to the promoter of SlGLK2 to inhibit its transcription, but also interacted with the SlGLK2 protein to inhibit the transcriptional activity of SlGLK2 and its downstream target genes. SlGLK2 knockout (KO-SlGLK2) plants exhibited a complete absence of the green shoulder, which was consistent with the fruit phenotype of OE-SlBEL2 plants. SlBEL2 showed an expression gradient in fruits, in contrast with that reported for SlGLK2. In conclusion, our study reveals that SlBEL2 affects the formation of green shoulder in tomato fruits by negatively regulating the gradient expression of SlGLK2, thus providing new insights into the molecular mechanism of fruit green shoulder formation.


Assuntos
Solanum lycopersicum , Solanum lycopersicum/metabolismo , Frutas/metabolismo , Fatores de Transcrição/metabolismo , Proteínas de Plantas/metabolismo , Ombro , Regulação da Expressão Gênica de Plantas
6.
Br J Cancer ; 129(2): 366-373, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37179440

RESUMO

BACKGROUND: Large cell lung carcinoma (LCLC) is an exceptionally aggressive disease with a poor prognosis. At present, little is known about the molecular pathology of LCLC. METHODS: Ultra-deep sequencing of cancer-related genes and exome sequencing were used to detect the LCLC mutational in 118 tumor-normal pairs. The cell function test was employed to confirm the potential carcinogenic mutation of PI3K pathway. RESULTS: The mutation pattern is determined by the predominance of A > C mutations. Genes with a significant non-silent mutation frequency (FDR) < 0.05) include TP53 (47.5%), EGFR (13.6%) and PTEN (12.1%). Moreover, PI3K signaling (including EGFR, FGRG4, ITGA1, ITGA5, and ITGA2B) is the most mutated pathway, influencing 61.9% (73/118) of the LCLC samples. The cell function test confirmed that the potential carcinogenic mutation of PI3K pathway had a more malignant cell function phenotype. Multivariate analysis further revealed that patients with the PI3K signaling pathway mutations have a poor prognosis (P = 0.007). CONCLUSIONS: These results initially identified frequent mutation of PI3K signaling pathways in LCLC and indicate potential targets for the treatment of this fatal type of LCLC.


Assuntos
Carcinoma de Células Grandes , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Fosfatidilinositol 3-Quinases/genética , Exoma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Mutação , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Receptores ErbB/genética , Pulmão
7.
Small ; 19(33): e2301364, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37086107

RESUMO

Construction of ferroelectric and optimization of macroscopic polarization has attracted tremendous attention for next generation light weight and flexible devices, which brings fundamental vitality for molecular ferroelectrics. However, effective molecular tailoring toward cations makes ferroelectric synthesis and modification relatively elaborate. Here, the study proposes a facile method to realize triggering and optimization of ferroelectricity. The experimental and theoretical investigation reveals that orientation and alignment of polar cations, dominated factors in molecular ferroelectrics, can be controlled by easily processed anionic modification. In one respect, ferroelectricity is induced by strengthened intermolecular interaction. Moreover, ≈50% of microscopic polarization enhancement (from 8.07 to 11.68 µC cm-2 ) and doubling of equivalent polarization direction (from 4 to 8) are realized in resultant ferroelectric FEtQ2ZnBrI3 (FEQZBI, FEtQ = N-fluoroethyl-quinuclidine). The work offers a totally novel platform for control of ferroelectricity in organic-inorganic hybrid ferroelectrics and a deep insight of structure-property correlations.

8.
Small ; 19(49): e2303127, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37625019

RESUMO

Organic-inorganic hybrid lead halide perovskites (OLHPs), represented by (CH3 NH3 )PbI3 , are one of the research focus due to their exceptional performance in optoelectronic applications, and ferroelastic domain walls are benign to their charge carrier transport that is confirmed recently. Among them, the 1D OLHPs feature better stability against desorption and moisture, but related 1D ones possessing ferroelasticity are rarely investigated and reported so far. In this work, the 1D ferroelastic semiconductor (N-iodomethyl-N-methyl-morpholinium)PbI3 ((IDMML)PbI3 ) is prepared successfully by introducing successively halogenate atoms from Cl, Br to I into the organic cation of the prototype (N,N-dimethylmorpholinium)PbI3 ((DMML)PbI3 ). Notably, (IDMML)PbI3 shows the narrow bandgap energy (≈2.34 eV) according to the ultraviolet-visible absorption spectrum and the theoretical calculation, and possesses the evident photoconductive characteristic with the on/off ratio of current of ≈50 under the 405 nm light irradiation. This work provides a new case for the ferroelastic OLHPs and will inspire intriguing research in the field of optoelectronic.

9.
Cancer Cell Int ; 23(1): 164, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37568192

RESUMO

OBJECTIVE: Systemic chemotherapy is the first-line therapeutic option for head and neck squamous cell carcinoma (HNSCC), but it often fails. This study aimed to develop an effective prognostic model for evaluating the therapeutic effects of systemic chemotherapy. METHODS: This study utilized CRISPR/cas9 whole gene loss-of-function library screening and data from The Cancer Genome Atlas (TCGA) HNSCC patients who have undergone systemic therapy to examine differentially expressed genes (DEGs). A lipid metabolism-related clustered polygenic model called the lipid metabolism related score (LMRS) model was established based on the identified functionally enriched DEGs. The prediction efficiency of the model for survival outcome, chemotherapy, and immunotherapy response was evaluated using HNSCC datasets, the GEO database and clinical samples. RESULTS: Screening results from the study demonstrated that genes those were differentially expressed were highly associated with lipid metabolism-related pathways, and patients receiving systemic therapy had significantly different prognoses based on lipid metabolism gene characteristics. The LMRS model, consisting of eight lipid metabolism-related genes, outperformed each lipid metabolism gene-based model in predicting outcome and drug response. Further validation of the LMRS model in HNSCCs confirmed its prognostic value. CONCLUSION: In conclusion, the LMRS polygenic prognostic model is helpful to assess outcome and drug response for HNSCCs and could assist in the timely selection of the appropriate treatment for HNSCC patients. This study provides important insights for improving systemic chemotherapy and enhancing patient outcomes.

10.
Inorg Chem ; 62(19): 7186-7194, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37128761

RESUMO

Hybrid lead halide perovskites have received extensive scientific attention owing to their great potential in the field of fluorescent displays and light-emitting diodes. Currently, most luminescent materials contain functional molecular and rare-earth metal ion parts. However, the mechanism of photoluminescence property in two-dimensional hybrid lead halide perovskites with different layered inorganic skeletons has been reported rarely. To better understand the effect of an inorganic skeleton on the fluorescence property, here, we report three organic-inorganic hybrid materials with different layered inorganic frameworks: (MACH)2·PbBr4 (Prv-1, MACH = cyclohexylmethylammonium), (2-MPQ)·PbBr4 (Prv-2, 2-MPQ = 2-methylpiperazinium), and (TMBA)4·Pb3Br10 (Prv-3, TMBA = N'N'N'-trimethylbenzylammonium). Among them, Prv-1 is a (100)-oriented perovskite, Prv-2 belongs to the (110)-oriented perovskite, and the inorganic framework of Prv-3 possesses [Pb3Br10] units. Interestingly, Prv-1 has a strong blue-violet fluorescence emission, while the luminescence effect of Prv-2 is very weak; notably, Prv-3 emits a charming bright-orange light. Meanwhile, results of theoretical computational studies also reveal that the electronic structure of all three compounds is highly dependent on structurally distorted [PbBr6] octahedra, and the frontier molecular orbital (FMO) analysis further suggests that HOMO and LUMO of Prv-3 are contributed by inorganic and organic components, respectively. In addition, all three materials belong to direct band gap semiconductors, and the band gaps are 2.79, 2.97, and 2.76 eV, respectively. Significantly, there are obvious differences in conduction bands. Based on the above analysis, the photoluminescence mechanism of three hybrid materials is explained from the electronic levels. Consequentially, this work might provide practical strategies and perspectives for exploring novel structure-related properties.

11.
Inorg Chem ; 62(29): 11701-11707, 2023 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-37427412

RESUMO

Switchable materials have attracted enormous interest due to their promising applications in important fields such as sensing, electronic components, and information storage. Nevertheless, obtaining multifunctional switching materials is still a problem worth investigating. Herein, by incorporating (Rac-, L-, D-2-amino-1-propanol) as the templating cation, we have obtained (Rac-, L-, D-HTMPA)CdCl3 (HTMPA = 1-hydroxy-N, N, N-trimethyl-2-propanaminium). We have adopted a chiral chemistry strategy that causes (Rac-HTMPA)CdCl3 in the central symmetric space to crystallize in the chiral space group. Based on the modulation of the homochiral strategy, (L-, D-HTMPA)CdCl3 shows a dual phasic transition at 269 and 326 K and a switchable second-harmonic generation response. In addition, (L-, D-HTMPA)CdCl3 is chiral switchable material to exhibit stable dual dielectric and second-harmonic generation (SHG) switches. This work provides an approach to exploring multifunctional chiral switchable materials.

12.
Inorg Chem ; 62(6): 2870-2876, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36706461

RESUMO

Compared with uniaxial molecular ferroelectrics, multiaxial ferroelectrics have better application prospects because they are no longer subject to the single-crystal form and have been pursued in recent years. Halogen engineering refers to the adjustment of halogens in materials at the atomic level, which can not only explore multiaxial ferroelectrics but also help to improve piezoelectrics, recently. In this work, we successfully synthesized and characterized three multiaxial plastic ferroelectrics through the precise molecular design from I to Cl, confirming the increase of the number of polar axes of ferroelectrics from 3 to 6, the increase of second-harmonic generation density from 2.1 times to nearly 6 times of monopotassium phosphate, and the increase of piezoelectric coefficient by 140%. This systematic work has proved that halogen engineering can not only enrich the family of multiaxial plastic ferroelectrics but also promote the further development of nonlinear optical and piezoelectric materials.

13.
Plant J ; 108(5): 1317-1331, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34580960

RESUMO

Fruit ripening in tomato (Solanum lycopersicum) is the result of selective expression of ripening-related genes, which are regulated by transcription factors (TFs). The NAC (NAM, ATAF1/2, and CUC2) TF family is one of the largest families of plant-specific TFs and members are involved in a variety of plant physiological activities, including fruit ripening. Fruit ripening-associated NAC TFs studied in tomato to date include NAC-NOR (non-ripening), SlNOR-like1 (non-ripening like1), SlNAC1, and SlNAC4. Considering the large number of NAC genes in the tomato genome, there is little information about the possible roles of other NAC members in fruit ripening, and research on their target genes is lacking. In this study, we characterize SlNAM1, a NAC TF, which positively regulates the initiation of tomato fruit ripening via its regulation of ethylene biosynthesis. The onset of fruit ripening in slnam1-deficient mutants created by CRISPR/Cas9 (clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9) technology was delayed, whereas fruit ripening in OE-SlNAM1 lines was accelerated compared with the wild type. The results of RNA-sequencing (RNA-seq) and promoter analysis suggested that SlNAM1 directly binds to the promoters of two key ethylene biosynthesis genes (1-aminocyclopropane-1-carboxylate synthase: SlACS2 and SlACS4) and activates their expression. This hypothesis was confirmed by electrophoretic mobility shift assays and dual-luciferase reporter assay. Our findings provide insights into the mechanisms of ethylene production and enrich understanding of the tomato fruit ripening regulatory network.


Assuntos
Etilenos/metabolismo , Regulação da Expressão Gênica de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Proteínas de Plantas/metabolismo , Solanum lycopersicum/genética , Frutas/genética , Frutas/fisiologia , Liases/genética , Liases/metabolismo , Solanum lycopersicum/fisiologia , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
14.
Mol Cancer ; 21(1): 25, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35057806

RESUMO

Primary lung cancer is one of the most common malignant tumors in China. Approximately 60% of lung cancer patients have distant metastasis at the initial diagnosis, so it is necessary to find new tumor markers for early diagnosis and individualized treatment. Tumor markers contribute to the early diagnosis of lung cancer and play important roles in early detection and treatment, as well as in precision medicine, efficacy monitoring, and prognosis prediction. The pathological diagnosis of lung cancer in small biopsy specimens determines whether there are tumor cells in the biopsy and tumor type. Because biopsy is traumatic and the compliance of patients with multiple biopsies is poor, liquid biopsy has become a hot research direction. Liquid biopsies are advantageous because they are nontraumatic, easy to obtain, reflect the overall state of the tumor, and allow for real-time monitoring. At present, liquid biopsies mainly include circulating tumor cells, circulating tumor DNA, exosomes, microRNA, circulating RNA, tumor platelets, and tumor endothelial cells. This review introduces the research progress and clinical application prospect of liquid biopsy technology for lung cancer.


Assuntos
Biomarcadores Tumorais , Biópsia Líquida , Neoplasias Pulmonares/diagnóstico , Animais , DNA Tumoral Circulante , Tomada de Decisão Clínica , Gerenciamento Clínico , Suscetibilidade a Doenças , Exossomos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Biópsia Líquida/métodos , Biópsia Líquida/normas , Neoplasias Pulmonares/etiologia , Neoplasias Pulmonares/terapia , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Prognóstico
15.
BMC Microbiol ; 22(1): 308, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36536275

RESUMO

BACKGROUND: The microbiome in the insect reproductive tract is poorly understood. Our previous study demonstrated the presence of Lactobacillus spp. in female moths, but their distribution and function remain unclear. Lactobacillus spp. are known as the 'healthy' vaginal microbiome in humans. RESULTS: Here, we studied the microbiome in the reproductive system (RS) and gut of Spodoptera frugiperda using 16S rDNA sequences. The obtained 4315 bacterial OTUs were classified into 61 phyla and 642 genera, with Proteobacteria, Firmicutes and Bacteroidota being the top three dominant phyla and Enterococcus and Asaia being dominant genera in most samples. Mating dramatically increased the abundance of pathogens or pathogenic functions in the gut, while in the RS, the change range was trivial. Taxonomy assignment identified thirteen Lactobacillus spp. in S. frugiperda, with Lactobacillus crustorum and Lactobacillus murinus showing high abundance. Three species found in S. frugiperda, namely L. reuteri, L. plantarum and L. brevis, have also been identified as human 'healthy' vaginal bacterial species. Lactobacillus spp. showed higher abundance in the RS of virgin females and lower abundance in the RS of virgin males and the gut of virgin females. Mating reduced their abundance in the RS of females but increased their abundance in the RS of males, especially in males mated with multiple females. The RS of virgin females and of multiple mated males were very similar in terms of composition and abundance of Lactobacillus species, with Lactobacillus crustorum showing much higher abundance in both tissues, potentially due to sexual transmission. CONCLUSIONS: Lactobacillus spp. showed high abundance and diversity in the RS of female moths. The higher abundance of Lactobacillus spp. in the RS of female moths and the similarity of Lactobacillus species in female moths with human 'healthy' vaginal Lactobacillus spp. suggest that these bacterial strains are also an important microbiome in the RS of female moths.


Assuntos
Acetobacteraceae , Microbioma Gastrointestinal , Mariposas , Masculino , Animais , Humanos , Feminino , Lactobacillus/genética , Vagina
16.
New Phytol ; 235(5): 1913-1926, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35686614

RESUMO

Flavor-imparting volatile chemicals accumulate as fruits ripen, making major contributions to taste. The NAC transcription factor nonripening (NAC-NOR) and DNA demethylase 2 (SlDML2) are essential for tomato fruit ripening, but details of the potential roles and the relationship between these two regulators in the synthesis of volatiles are lacking. Here, we show substantial reductions in fatty acid and carotenoid-derived volatiles in tomato slnor and sldml2 mutants. An unexpected finding is the redundancy and divergence in volatile profiles, biosynthetic gene expression, and DNA methylation in slnor and sldml2 mutants relative to wild-type tomato fruit. Reduced transcript levels are accompanied by hypermethylation of promoters, including the NAC-NOR target gene lipoxygenase (SlLOXC) that is involved in fatty acid-derived volatile synthesis. Interestingly, NAC-NOR activates SlDML2 expression by directly binding to its promoter both in vitro and in vivo. Meanwhile, reduced NAC-NOR expression in the sldml2 mutant is accompanied by hypermethylation of its promoter. These results reveal a relationship between SlDML2-mediated DNA demethylation and NAC-NOR during tomato fruit ripening. In addition to providing new insights into the metabolic modulation of flavor volatiles, the outcome of our study contributes to understanding the genetics and control of fruit ripening and quality attributes in tomato.


Assuntos
Solanum lycopersicum , DNA , Ácidos Graxos/metabolismo , Frutas/genética , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/metabolismo , Proteínas de Plantas/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Chemistry ; 28(40): e202200579, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35467772

RESUMO

Hybrid organic-inorganic perovskite (HOIP) have received tremendous scientific attention because of the phase transition and photovoltaic properties. However, achieving the special perovskite structure with both two-step dielectric response and luminescence characteristics is rarely reported. Herein, we report an organic-inorganic hybrid perovskite, [(BA)2 ⋅ PbI4 ] (Compound 1, BA=n-butylamine) by introducing flexible organic cations (HBA+ ), with direct mid-band gap as 2.28 eV. Interestingly, this material exhibits two-step reversible dielectric response at 350 K and 460 K (in heating process), respectively. Besides, the photoluminescence was found: it emits charming green light under 365 nm lamp (Photoluminescence quantum yield is 9.52 %). The outstanding two-step dielectric response and luminescence characteristics of this compound might pave the way for the application of dielectric and ferroelectric functional materials in temperature sensors and mechanical switches.

18.
Chemistry ; 28(59): e202201005, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-35790034

RESUMO

Molecular ferroelastics have received particular attention for potential applications in mechanical switches, shape memory, energy conversion, information processing, and solar cells, by taking advantages of their low-cost, light-weight, easy preparation, and mechanical flexibility. The unique structures of organic-inorganic hybrid perovskites have been considered to be a design platform for symmetry-breaking-associated order-disorder in lattice, thereby possessing great potential for ferroelastic phase transition. Herein, we review the research progress of organic-inorganic hybrid perovskite ferroelastics in recent years, focusing on the crystal structures, dimensions, phase transitions and ferroelastic properties. In view of the few reports on molecular-based hybrid ferroelastics, we look forward to the structural design strategies of molecular ferroelastic materials, as well as the opportunities and challenges faced by molecular-based hybrid ferroelastic materials in the future. This review will have positive guiding significance for the synthesis and future exploration of organic-inorganic hybrid molecular ferroelastics.

19.
Chemistry ; 28(69): e202202533, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36082618

RESUMO

Organic-inorganic Hybrid (OIH) materials for multifunctional switchable applications have attracted enormous attention in recent years due to their excellent optoelectronic properties and good structural tunability. However, it still remains challenging to fabricate one simple OIH compound with multi-functionals properties, such as dielectric switching, thermochromic properties, semiconductor characteristics and ferroelasticity. Under this context, we successfully synthesized [2-(2-fluorophenyl)ethan-1- ammonium]2 SnBr6 (compound 1), which has a higher phase transition temperature of 427.7 K. Additionally, it exhibits a semiconducting property with an indirect band gap of 2.36 eV. Combining ferroelastic, narrow band gap, thermochromic, and dielectric properties, compound 1 can be considered as a rarely reported multi-functional ferroelastic material, which is expected to give inspiration for broadening the applications in the smart devices field.


Assuntos
Semicondutores , Transição de Fase
20.
Inorg Chem ; 61(28): 10872-10879, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35792734

RESUMO

Organic-inorganic hybrid materials with switchable properties have significant potential applications in intelligent devices. There are some conventional ways to obtain optical and/or electric multiple responses, such as asymmetric design, chirality, doping, and structural dimension in hybrid materials. Among them, the homochirality strategy is one of the best ways to regulate the molecular structure and symmetry, thereby ensuring second-harmonic generation (SHG) and dielectric dual response characteristics. Here, we report a homochiral design strategy to obtain noncentrosymmetric [R-(HASD)][Cd(SCN)3] (HASD = 7-hydroxy-5-azaspiro[4.5]decan) and [S-(HASD)][Cd(SCN)3]; [Rac-(HASD)][Cd(SCN)3] was also synthesized as a comparative experiment to illustrate the relationship between structural chirality and physical properties. With the help of homochiral regulation, the SHG response is excited and dielectric phase transition temperature (Tc) is also highly improved. In addition, both the optical SHG and dielectric phase change show an optical/electric switchable response. This work is of great significance for the further exploration of multifunctional molecular switching materials through homochiral chemistry.

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