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1.
Inorg Chem ; 63(40): 18955-18962, 2024 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-39308097

RESUMO

Inorganic-organic hybrid bismuth halides demonstrate great prospect in the field of second-order nonlinear optical (NLO) crystals because the ns2 electron on Bi(III) could lead to large molecular polarization and high second harmonic generation (SHG) coefficient on a noncentrosymmetric structure. However, researchers cannot yet control the effective arrangements of the bismuth halide functional motif, which results in SHG-active hybrid bismuth halides being rare. Herein, thiazole derivatives with a polar donor-π-acceptor system are designed to explore hybrid bismuth halide NLO crystals. The protonated 2-(4-hydroxyphenyl) thiazole (denoted as hpt) interacts with the (BiCl6) motif via H···Cl hydrogen bonds to prevent antiparallel arrangements, which therefore enhance the NLO property. (Hhpt)3[BiCl6] crystallizes in the monoclinic polar P21 space group, which exhibits a strong SHG response and reversible photochromic behavior. Structural analysis and theory calculations reveal that the synergistic effect between the polar thiazole derivative and the distorted inorganic [BiCl6]3- motif is responsible for the SHG response. This is the first report of polar thiazole derivative-induced SHG-active hybrid bismuth halide coupled with reversible photochromism.

2.
Inorg Chem ; 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356130

RESUMO

Two Co(II) metal-organic frameworks (Co-MOFs), namely, [Co(DMTDC)(bimb)]n (Co-MOF-1) and {[Co(DPTDC)(bimb)(H2O)]·2DMF}n (Co-MOF-2) (H2DMTDC = 3,4-dimethylthieno[2,3-b]thiophene-2,5-dicarboxylic acid, H2DPTDC = 3,4-diphenylthieno[2,3-b]thiophene-2,5-dicarboxylic acid, bimb = 1,4-bis((1H-imidazol-1-yl)methyl)benzene), were obtained by the reaction of flexible N-containing ligand bimb and two structurally related thiophene-containing ligands H2DMTDC and H2DPTDC, respectively. These Co-MOFs displayed a 3D framework and porous structure, respectively. Co-MOF-1 and the activated sample Co-MOF-2' could act as green heterogeneous catalysts for the one-pot multicomponent Biginelli reaction, specifically the dehydration condensation process involving aldehydes, acetoacetates, and urea to yield dihydropyrimidin-2(1H)-ones. The reaction has advantages such as solvent-free conditions, water as only byproduct, readily accessible starting materials, excellent functional group compatibility, and simple operation. Both catalysts exhibited a wide substrate scope and maintained significant catalytic activity over five cycles. The special catalytic performance may be ascribed to functional groups within the ligand.

3.
Mol Phylogenet Evol ; 189: 107914, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37666378

RESUMO

Phylogenetic studies in the phylogenomics era have demonstrated that reticulate evolution greatly impedes the accuracy of phylogenetic inference, and consequently can obscure taxonomic treatments. However, the systematics community lacks a broadly applicable strategy for taxonomic delimitation in groups characterized by pervasive reticulate evolution. The red-fruit genus, Stranvaesia, provides an ideal model to examine the influence of reticulation on generic circumscription, particularly where hybridization and allopolyploidy dominate the evolutionary history. In this study, we conducted phylogenomic analyses integrating data from hundreds of single-copy nuclear (SCN) genes and plastomes, and interrogated nuclear paralogs to clarify the inter/intra-generic relationship of Stranvaesia and its allies in the framework of Maleae. Analyses of phylogenomic discord and phylogenetic networks showed that allopolyploidization and introgression promoted the origin and diversification of the Stranvaesia clade, a conclusion further bolstered by cytonuclear and gene tree discordance. With a well-inferred phylogenetic backbone, we propose an updated generic delimitation of Stranvaesia and introduce a new genus, Weniomeles. This new genus is distinguished by its purple-black fruits, thorns trunk and/or branches, and a distinctive fruit core anatomy characterized by multilocular separated by a layer of sclereids and a cluster of sclereids at the top of the locules. Through this study, we highlight a broadly-applicable workflow that underscores the significance of reticulate evolution analyses in shaping taxonomic revisions from phylogenomic data.


Assuntos
Sonhos , Rosaceae , Filogenia , Rosaceae/genética
4.
Inorg Chem ; 62(19): 7324-7332, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37130306

RESUMO

Negative temperature coefficient (NTC) thermistors feature higher sensitivities and faster response speeds and thereby have particular applications in many fields. However, current NTC thermistors are mostly based on inorganic ceramic materials, which show obvious drawbacks in material synthesis, property modulation, and flexible film fabrication. Herein, we report, for the first time, the promising application of an inorganic-organic hybrid NTC thermistor. A new lead-free hybrid iodo bismuthate [1,1',1″-(benzene-1,3,5-triyl)tris(3-methyl-1H-imidazol-3-ium)]Bi2I9 [denoted as (Me3TMP)Bi2I9] was synthesized by a "double-free" strategy. (Me3TMP)Bi2I9 features a lead-free binuclear bismuth iodine anion charge compensated by a "classic hydrogen-bond-free" cation. (Me3TMP)Bi2I9 exhibits remarkable stability in water and UV light irradiation and shows the largest temperature sensitivity coefficient among all reported NTC materials. Theoretical calculation and detailed structural analysis disclose that the seriously distorted (BiI6) octahedra are responsible for the intriguing NTC effect for (Me3TMP)Bi2I9.

5.
Altern Ther Health Med ; 29(8): 770-775, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37708551

RESUMO

Objective: This study aimed to investigate the clinical effectiveness of the SilverFlow branch stent through endovascular isolation and in situ fenestration (ISF) for the treatment of aortic dissection (AD) involving the aortic arch. Methods: A total of 21 patients with AD involving the aortic arch, admitted to our hospital between September 2021 and January 2023, were selected for this prospective study. All patients underwent treatment with an endoluminal isolated ISF-covered stent, with the branch stent being the SilverFlow, developed by Shenzhen Xianjian Company. We assessed the success rate of the ISF procedure stent-related complications and compared the volumes of the true and false cavities before and after treatment. Follow-up evaluations were conducted 1, 3, and 6 months post-operation, focusing on neurological complications, mortality, and the need for secondary interventional treatment. Results: Among the 21 AD patients with aortic arch involvement, 20 (95.23%) underwent non-emergency surgery, while 1 (4.76%) required emergency surgery due to cardiac ischemia and signs of dissection rupture. All surgeries were successfully completed. After treatment, the average volume of the true lumen significantly decreased compared to pre-treatment levels, while the volume of the false lumen significantly increased (P < .05). The success rate was 100%, with only one case (4.76%) experiencing type I internal leakage. There were no cases of stent displacement, distortion, or fenestration vessel occlusion. One patient (4.76%) succumbed to acute pericardial tamponade, resulting in a mortality rate of 4.76%. Another patient (4.76%) suffered from upper limb ischemia, significantly improving with antithrombotic drug treatment. No occurrences of stroke, visceral ischemia, or other complications were reported, and no secondary interventional treatments were required. Conclusions: The application of the SilverFlow branch stent for endovascular isolation of ISF in AD cases involving the aortic arch demonstrates a high success rate, low complication and mortality rates, and significant clinical feasibility and value.


Assuntos
Aneurisma da Aorta Torácica , Dissecção Aórtica , Implante de Prótese Vascular , Humanos , Prótese Vascular , Implante de Prótese Vascular/métodos , Estudos Prospectivos , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/cirurgia , Stents , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia , Resultado do Tratamento , Isquemia/cirurgia , Estudos Retrospectivos
6.
Inorg Chem ; 56(4): 1906-1918, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28169534

RESUMO

In situ alkylation or protonation reactions on the thiazolyl-N donors of benzothiazole (btz) and its derivative 2-aminobenzothiazole (abtz) occurred to form four structure directing agents (SDAs), which feature different structure directing abilities and hydrophobicities. The thiazolyl-N alkylated and protonated btz cations direct to form an α-type (AgI2)- iodoargentate chain in (Etbtz)(AgI2) (1), (Prbtz)(AgI2) (2), and (Hbtz)(AgI2) (3), respectively, while the thiazolyl-N protonated abtz cation directs to form a new type of (Ag2I3)- anionic chain in (Habtz)(Ag2I3) (4). Compounds 1 and 4 represent the first noncentrosymmetric (NCS) hybrid iodoargentates with organic S-containing N-heterocycle derivative cations as SDAs. Further, 1 exhibits high water stability and is second harmonic generation (SHG) active with a response about twice that of KDP (KH2PO4). Importantly, the water stability studies indicate that hybrid iodoargentates with hydrophobic N-alkylated SDAs are more stable in water than those with relative hydrophilic N-protonated SDAs.

7.
Dalton Trans ; 53(8): 3654-3665, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38289280

RESUMO

Two new metal-organic frameworks (MOFs), namely, {[Zn(HL)(bpea)]·DMF}n (Zn-MOF-1) and {[Co(HL)(bpea)]·DMF}n (Co-MOF-2) (H3L = 3-(3,5-dicarboxybenzyloxy)benzoic acid, bpea = 1,2-di(pyridyl)ethane), were obtained by the reaction of H3L and N-containing ligand bpea with Zn(NO3)2·6H2O and Co(NO3)2·6H2O, respectively. The isomorphic Zn-MOF-1 and Co-MOF-2 featured a 3D penetrating framework with different stabilities, luminescence, and catalytic properties. Luminescence measurement indicated that Zn-MOF-1 could be used to detect Al3+ through a turn-on effect with a detection limit of 0.42 µM. The sensing mechanism experiments showed that the enhanced luminescence of Zn-MOF-1 toward Al3+ may be due to the weak interaction between Al3+ and Zn-MOF-1 and the absorbance-caused enhancement (ACE) mechanism. Meanwhile, both Zn-MOF-1 and Co-MOF-2 showed interesting CO2 adsorption properties and could catalyze the cycloaddition of CO2 to epoxides resulting in 96 and 92% ideal products within 12 hours, respectively. They can be cycled up to 5 times without significant loss of catalytic efficiency.

8.
Dalton Trans ; 53(36): 15330-15337, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39224942

RESUMO

The stable contact of heterogeneous interfaces and the substantial exposure of active sites are crucial for enhancing the photocatalytic performance of semiconductor catalysts. However, most reported two-dimensional (2D)/2D CsPbBr3 and BiOCl heterostructures are fabricated using electrostatic self-assembly methods, which exhibit significant deficiencies in precise interface quality control and effective active site exposure. In this study, we fabricate a zero-dimensional (0D)/2D CsPbBr3/BiOCl heterojunction via a two-step calcination method, achieving an efficient direct S-scheme configuration. Optimizing interfacial contact and band alignment between CsPbBr3 quantum dots and BiOCl nanosheets enhances cross-plane charge transfer, promoting superior charge separation. This 0D/2D CsPbBr3/BiOCl heterojunction exhibits enhanced carrier mobility and high conversion rates without cocatalysts or sacrificial agents. The mechanism underlying the accelerated S-scheme charge transfer is comprehensively elucidated through a combination of analytical techniques and density functional theory (DFT) calculations. This study offers a novel approach for managing charge carrier segregation and mobility in CO2 reduction photocatalysts.

9.
PhytoKeys ; 242: 161-227, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38854497

RESUMO

This study addresses the longstanding absence of a comprehensive phylogenetic backbone for the apple tribe Maleae, a deficiency attributed to limited taxon and marker sampling. We conducted an extensive taxon sampling, incorporating 563 plastomes from a diverse range of 370 species encompassing 26 presently recognized genera. Employing a range of phylogenetic inference methods, including RAxML and IQ-TREE2 for Maximum Likelihood (ML) analyses, we established a robust phylogenetic framework for the Maleae tribe. Our phylogenomic investigations provided compelling support for three major clades within Maleae. By integrating nuclear phylogenetic data with morphological and chromosomal evidence, we propose an updated infra-tribal taxonomic system, comprising subtribe Malinae Reveal, subtribe Lindleyinae Reveal, and subtribe Vauqueliniinae B.B.Liu (subtr. nov.). Plastid phylogenetic analysis also confirmed the monophyly of most genera, except for Amelanchier, Malus, Sorbus sensu lato, and Stranvaesia. In addition, we present a comprehensive taxonomic synopsis of Photinia and its morphological allies in the Old World, recognizing 27 species and ten varieties within Photinia, three species and two varieties within Stranvaesia, and two species and three varieties within Weniomeles. Furthermore, we also lectotypified 12 names and made two new combinations, Photiniamicrophylla (J.E.Vidal) B.B.Liu and Weniomelesatropurpurea (P.L.Chiu ex Z.H.Chen & X.F.Jin) B.B.Liu.

10.
PhytoKeys ; 229: 47-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37457385

RESUMO

Docynia has been treated as a separate genus or merged into Cydonia or Docyniopsis. Our phylogenomic evidence from 797 single-copy nuclear genes and plastomes confirmed the sister relationship between Docynia and Docyniopsis. By integrating the phylogenomic and morphological evidence, we propose to accept a broad generic concept of Malus and merge Docynia into Malus. Three new combinations are also made here: Malusdelavayi (Franch.) B.B.Liu, M.indica (Wall.) B.B.Liu and M.longiunguis (Q.Luo & J.L.Liu) B.B.Liu.

11.
Inorg Chem ; 51(1): 472-82, 2012 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-22148320

RESUMO

The exploration in two hydro(solvo)thermal reaction systems As/S/Mn(2+)/phen/methylamine aqueous solution and As/S/Mn(2+)/2,2'-bipy/H(2)O affords five new manganese thioarsenates with diverse structures, namely, (CH(3)NH(3)){[Mn(phen)(2)](As(V)S(4))}·phen (1 and 1'), (CH(3)NH(3))(2){[Mn(phen)](2)(As(V)S(4))(2)} (2), {[Mn(phen)(2)](As(III)(2)S(4))}(n) (3), {[Mn(phen)](3)(As(III)S(3))(2)}·H(2)O (4), and {[Mn(2,2'-bipy)(2)](2)(As(V)S(4))}[As(III)S(S(5))] (5). Compound 1 comprises a {[Mn(phen)(2)](As(V)S(4))}(-) complex anion, a monoprotonated methylamine cation and a phen molecule. Compound 2 contains a butterfly like {[Mn(phen)](2)(As(V)S(4))(2)}(2-) anion charge compensated by two monoprotonated methylamine cations. Compound 3 is a neutral chain formed by a helical (1)(∞)(As(III)S(2)(-)) vierer chain covalently bonds to [Mn(II)(phen)](2+) complexes via all its terminal S atoms. Compound 4 features a neutral chain showing the stabilization of noncondensed (As(III)S(3))(3-) anions in the coordination of [Mn(II)(phen)](2+) complex cations. Compound 5 features a mixed-valent As(III)/As(V) character and an interesting chalcogenidometalates structure, where a polycation formed by the connection of two [Mn(2,2'-bipy)(2)](2+) complex cation and a (As(V)S(4))(3-) anion acts as a countercation for a polythioarsenate anion, [As(III)S(S(5))](-). The title compounds exhibit optical gaps in the range 1.58-2.48 eV and blue photoluminescence. Interestingly, compound 1 displays a weak second harmonic generation (SHG) response being about 1/21 times of KTP (KTiOPO(4)). Magnetic measurements show paramagnetic behavior for 1 and dominant antiferromagnetic behavior for 2-5. Of particular interest is 4, which is the first manganese chalcogenide showing spin-canting characteristic.

12.
Chem Commun (Camb) ; 58(17): 2858-2861, 2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35129567

RESUMO

We report the thinnest copper sulfur atomic monolayer in an organic copper chalcogenide [Cu(CMP)]n (CMP = 5-chloro-2-mercaptopyridine). The layer features a new type of copper sulfur structure woven by both covalent bond and cuprophilic interaction and shows an intriguing oriented photoconductivity.

13.
Inorg Chem ; 50(12): 5740-6, 2011 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-21598930

RESUMO

A novel one-dimensional (1-D) mixed-valent thioarsenate (III, V), {[Mn(phen)](3)(As(V)S(4))(As(III)S(3))}(n)·nH(2)O (1), with a noncentrosymmetric (NCS) polar packing arrangement has been obtained under solvothermal conditions. The noncondensed (As(III)S(3))(3-) anion in 1 is stabilized by coordinating to [Mn(II)(phen)](2+) complex cations and exhibits an unprecedented µ(3)-1,2κS:2,3κS':3κS'' linkage mode. Compound 1 represents the first example of the stabilization of noncondensed (MQ(3))(3-) (M = As, Sb; Q = S, Se) species only in the coordination of TM(II) complex cations (TM = transition-metal) and the first observation of the coexistence of the (As(V)S(4))(3-) tetrahedron and the noncondensed (As(III)S(3))(3-) pyramid in a single compound. Of particular interest, compound 1 is also an antiferromagnet with T(N) = 31 K, and exhibits photoluminescence (PL) with a maximum emission at about 438 nm and a second harmonic generation (SHG) response.

14.
Inorg Chem ; 50(19): 9660-9, 2011 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-21902192

RESUMO

1,10-Phenanthroline (phen) and monoprotonated methylamine molecules were used as a novel cotemplate to direct the formation of a new inorganic-organic hybrid selenidostannate, (CH(3)NH(3))(4)(Sn(2)Se(6))·6phen (1); while the utilization of three types of transition-metal (TM) phen complex cations with the TM/phen ration of 1:1, 1:2, and 1:3 as structure directors affords {[Mn(phen)(2)](2)(µ(2)-Sn(2)Se(6))}·H(2)O (2a), {[Fe(phen)(2)](2)(µ(2)-Sn(2)Se(6))} (2b), {[Mn(phen)](2)(µ(4)-Sn(2)Se(6))}(n) (3), {[Mn(phen)(2)](Sn(2)Se(5))}(n) (4), and [Fe(phen)(3)](n)(Sn(3)Se(7))(n)·1.25nH(2)O (5). These compounds show diverse structures with the selenidostannate anions varying from discrete, µ(2)- and µ(4)- (Sn(2)Se(6))(4-) anions, to one-dimensional (1-D) (1)(∞)(Sn(2)Se(5)(2-)) anionic chains, and two-dimensional (2-D) extended (2)(∞)(Sn(3)Se(7)(2-)) anionic layers, demonstrating different structure-directing abilities of the cotemplate and the three types of TM phen complex cations. This work clearly indicates that the approach of modifying the number of the free coordination sites of unsaturated TM phen complex cations is very exciting as a way to synthesize novel hybrid chalcogenidometalates. Of particular interest, the present compounds exhibit interesting optical properties that reflect the combined effects of both photoluminescence-active organic components and semiconducting inorganic chalcogenidometalate anionic networks.

15.
Environ Pollut ; 290: 118119, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34523528

RESUMO

Although groundwater nitrogen pollution has been widely studied, the control of hydrogeological conditions on behavior of nitrogen compounds has been poorly understood. In this study, multiple stable isotopes (N/C/H/O), spectral characteristics of DOM coupled with water chemistry were used to reveal the sources and fate of nitrate and ammonium in three subareas with different hydrogeological conditions in the Central Yangtze River Basin. We identified three contrasting patterns of nitrogen sources and fate in groundwater controlled by different aquifer features. In a reducing porous aquifer mainly composed of carbonate minerals overlain by a thick low-permeability layer, the NH4-N concentration is high (mean 4.12 mg/L) but with quite low NO3-N concentration (mean 0.28 mg/L). The high ammonium is mainly from intense degradation of organic matter (OM), while denitrification at a higher rate results in nitrate removal. Feammox may be favored owing to abundant humics acting as the electron shuttle. In a weakly reducing to oxidizing porous aquifer mainly composed of aluminosilicate minerals overlain by a varying thickness of low-permeability layer, high ammonium occurs in a weakly reducing condition and is affected by both anthropogenic input and OM degradation, while high nitrate occurs in a more oxidizing condition and could be mainly from soil nitrogen, manure or sewage. Feammox may be also favored due to more acidic environment formed by weathering of aluminosilicate minerals, fluctuating redox condition and low abundance of labile organic carbon, while denitrification occurs at a slower rate coupled with concurrent re-oxidation of nitrite to nitrate. In an oxidizing porous - fissured aquifer system overlain by a thin low-permeability layer, the concentrations of ammonium and nitrate are both low, possibly due to strong hydrodynamic and flushing condition, although slightly higher concentration of nitrate exhibit similar sources and fate with the weakly reducing to oxidizing porous aquifer mentioned above.


Assuntos
Água Subterrânea , Poluentes Químicos da Água , Monitoramento Ambiental , Nitratos/análise , Nitrogênio/análise , Compostos de Nitrogênio , Isótopos de Nitrogênio/análise , Rios , Poluentes Químicos da Água/análise
16.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): m758, 2010 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-21587693

RESUMO

The asymmetric unit of the title Cd(II) compound, [Cd(N(3))(2)(C(12)H(8)N(2))](n), contains a Cd(II) atom, located on a twofold axis passing through the middle of the phenanthroline mol-ecule, one azide ion and half of a 1,10-phenanthroline mol-ecule. The Cd(II) atom exhibits a distorted octa-hedral coordin-ation including one chelating 1,10-phenanthroline ligand and four azide ligands. The crystal structure features chains along the c direction in which azide groups doubly bridge two adjacent Cd(II) atoms in an end-on (EO) mode. Inter-chain π-π stacking inter-actions, with centroid-centroid separations of 3.408 (2) Šbetween the central aromatic rings of 1,10-phenanthroline mol-ecules, lead to a supra-molecular sheet parallel to the bc plane.

17.
PhytoKeys ; 139: 99-118, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32089637

RESUMO

As part of a comprehensive systematic study on the genus Eriobotrya and its close relatives from the E & SE Asia, new typifications of 23 names are presented here, along with some nomenclatural notes of the names involved. We lectotypified 22 names including accepted names and synonyms. They are: E. acuminatissima, E. bengalensis var. angustifolia; E. bengalensis f. intermedia, E. brackloi, E. brackloi var. atrichophylla, E. elliptica var. petelotii, E. fragrans var. furfuracea, E. glabrescens, E. grandiflora, E. henryi, E. oblongifolia, E. petiolata, E. platyphylla, E. poilanei, E. prinoides, E. prinoides var. laotica, E. salwinensis, E. serrata, E. stipularis, Hiptage cavaleriei, Photinia longifolia, Symplocos seguinii. One neotype of Photinia dubia was also proposed in this study, and E. pseudoraphiolepis and Mespilus cuila were identified as superfluous names. In addition, we also summarized the typification of 18 names for taxonomic reference: E. angustissima, E. balgooyi, E. condaoensis, E. × daduheensis, E. elliptica, E. fulvicoma, E. fragrans, E. glabrescens var. victoriensis, E. hookeriana, E. latifolia, E. obovata, E. malipoensis, E. merguiensis, E. tengyuehensis, E. wardii, Mespilus bengalensis, Photinia deflexa, and M. japonica.

18.
Mitochondrial DNA B Resour ; 5(1): 798-799, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-33366756

RESUMO

The chloroplast genome of the Magnolia species from Central America has never been reported. With its local use for food flavoring, medicine, and wood, M. mexicana has been of good economic importance. In the present study, the complete chloroplast genome of M. mexicana was assembled via the genome skimming data. As a typical quadripartite structure, the plastome of M. mexicana with 159,906 bp in length includes two inverted repeats (26,554 bp) separated by a small single copy region (18,761 bp) as well as a large single copy region (88,037 bp). This chloroplast genome consists of 131 different genes, including 86 protein coding genes (CDS), eight rRNA genes, and 37 tRNA genes. The maximum likelihood phylogenetic analysis showed that M. mexicana from Central America was closely related to an evergreen species, M. odoratissima from East Asia.

19.
RSC Adv ; 10(17): 10023-10029, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35498579

RESUMO

Compared with nanoscale quantum dots (QDs), the large-sized perovskite crystals not only possess better stability but also are convenient for application exploration. Herein, we develop a facile and efficient antisolvent vapor-assisted recrystallization approach for the synthesis of large-sized Cs4PbBr6 perovskite crystal microplates. In this method, for the first time, the shale-like Cs4PbBr6 microplates with lateral dimensions of hundreds of microns are fabricated by employing cetyltriethylammnonium bromide (CTAB) as a morphology-directing agent. FESEM, TEM, and AFM characterizations indicate that the as-obtained shale-like Cs4PbBr6 microplates are actually formed by 6-8 nm thick Cs4PbBr6 nanosheets with orientational stacking. Importantly, such highly crystalline Cs4PbBr6 microplates with shale-like morphology exhibit a narrow and intense green PL emission with a 59% PL quantum yield. Moreover, the planar structure of shale-like Cs4PbBr6 microplates makes it easy to form a preferred orientation on a substrate, which endow them with promising potential in optoelectronic devices such as lighting and displays.

20.
ACS Appl Mater Interfaces ; 12(49): 54694-54702, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33216521

RESUMO

The employment of hybrid perovskite MAPbX3 (MA = CH3NH3+, X = Br or I) as photocatalysts in a photocatalytic hydrogen evolution reaction represents a promising approach to store solar energy. However, the toxicity of Pb makes these materials difficult to pass environmental evaluation while the intrinsic moisture sensitivity puts forward high anhydrous requirements in photocatalysts synthesis, storage, and application, which further reduces their service life. Herein, we demonstrate a hydrogen-bond-free strategy to synthesize moisture-stable hypotoxic hybrid perovskite for photocatalytic application by replacing traditional protonated countercations with alkylated countercations in a Pb-free hybrid system, which prevents water eroding hybrid perovskites via strong hydrogen bonds. A zero-dimensional Bi-based perovskite (3-ethylbenzo[d]thiazol-3-ium)4Bi2I10 (EtbtBi2I10) was synthesized, which contains dimeric (Bi2I10)4- formed by edge-sharing (BiI6) octahedra being different from the binuclear cluster in widely studied MA3Bi2I9. Theoretical calculations indicate that the electron communication between inorganic and organic moieties is responsible for its broadband absorption with a narrow band gap of 2.04 eV. EtbtBi2I10 exhibits excellent stability in distilled water, moisture air, acid solution, and UV-light irradiation. It shows effective photocatalytic performance in HI splitting to generate hydrogen with the performance comparable with MAPbI3. Introducing electron and hole-transporting channels drastically enhances the photocatalytic reaction.

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