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1.
J Environ Manage ; 330: 117134, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36584459

RESUMO

Recently, the major environmental pollution produced by the release of wastewater in liquid type is one of the most extensive forms of foremost pollution in water ecosystems. In this article, the Bi2O3/g-C3N4 nanocomposite with a direct Z-scheme was effectively obtained by a facile hydrothermal system. The crystal structures, surface morphology, chemical composition, and the optical belongings of the as-obtained composite catalysts were examined by Power XRD, FT-IR spectra, High-resolution XPS spectra, FE-SEM images with EDX spectra, High-resolution TEM images, UV-Vis DRS, and PL spectra respectively. Furthermore, the photocatalytic performance was assessed by the degradation of aqueous Rhodamine B (Rh B) dye under visible-light exposure. The Bi2O3/g-C3N4 composite photocatalysts (PCs) showed the maximum photo-degradation efficiency through a rate constant value of 0.0149 min-1, which is 4.9 and 5.3 folds superior to Bi2O3, and GCN, respectively. The better GBO2 nanocomposite PCs showed a superior photocatalytic degradation performance (>82%) of aqueous Rh B dye after five successive recycles. Moreover, based on these outcomes of the radical scavenging test, a direct and effective Z-scheme photocatalytic charger transfer mechanism was also projected. Finally, the reusability of the as-obtained Bi2O3/g-C3N4 nanocomposite has better stability and reusability, which was a favourable applicant for wastewater handling.


Assuntos
Ecossistema , Nanopartículas , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Fontes de Energia Elétrica , Água
2.
Artigo em Inglês | MEDLINE | ID: mdl-22446789

RESUMO

Crystals of a new nonlinear optical (NLO) material, viz., L-asparagine-L-tartaric acid (LALT) (1) were grown by slow evaporation of an aqueous solution containing equimolar concentrations of L-asparagine and L-tartaric acid. The structure of the title compound which crystallizes in the non-centrosymmetric monoclinic space group P2(1) consists of a molecule of L-asparagine and a molecule of free l-tartaric acid both of which are interlinked by three varieties of H-bonding interactions namely O-H···O, N-H···O and C-H···O. The UV-Vis-NIR spectrum of 1 reveals its transparent nature while the vibrational spectra confirm the presence of the functional groups in 1. The thermal stability and second harmonic generation (SHG) conversion efficiency of 1 were investigated.


Assuntos
Asparagina/química , Tartaratos/química , Cristalização , Ligação de Hidrogênio , Modelos Moleculares , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura
3.
ISRN Org Chem ; 2011: 541082, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-24052824

RESUMO

The crystal structures of 4-(4-methylphenyl)-6-phenyl-2,3,3a,4-tetrahydro-1H-pyrido[3,2,1-jk]carbazole (IIa) and 4-(4-methoxyphenyl)-6-phenyl-2,3,3a,4-tetrahydro-1H-pyrido[3,2,1-jk]carbazole (IIb) were elucidated by single crystal X-ray diffraction. Compound (IIa), C28H25N, crystallizes in the triclinic system, space group P-1, with a = 8.936(2) Å, b = 10.490(1) Å, c = 11.801(1) Å, α = 102.69(5) (°) ,  ß = 103.27(3) (°) , γ = 93.80(1) (°) , and Z = 2. The compound (IIb), C28H25NO, crystallizes in the monoclinic system, space group P21/a, with a = 11.376(5) Å, b = 14.139(3) Å, c = 13.237(4) Å, ß = 97.41(3) (°) , and Z = 4. In both the structures, the pyrido ring adopts a twist boat conformation and the carbazole molecule has the twisted envelope structure with C3 and C13 at the flap. No classical hydrogen bonds are observed in the crystal structures. Details of the preparation, structures, and spectroscopic properties of the new compounds are discussed.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 77(1): 160-3, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20537939

RESUMO

A new and efficient organic nonlinear optical (NLO) crystal from the amino acid family, viz., l-threoninium picrate (LTHP), has been grown by solvent evaporation technique from aqueous solution. The structure of LTHP was elucidated using single crystal X-ray diffraction data. The compound crystallized in the non-centrosymmetric space group P2(1) and the unit cell contains two l-threoninium cations and two picrate anions. The backbone conformation angles Psi(1) and Psi(2) are in cis and trans configurations for both the picrate and the threoninium residues. An intra-molecular hydrogen bond between the amine N atom and the nearby oxygen atom, viz., N1-H1B(...)O3 is observed, with a graph set motif R(1)(1)(5). The second harmonic generation (SHG) efficiency of this material was measured using Kurtz and Perry method and found to be about 43 times that of standard potassium dihydrogen phosphate (KDP) crystals. Fourier transform infrared (FTIR) and ultraviloet-visible-near infrared spectral studies were also carried out. The details are discussed.


Assuntos
Modelos Químicos , Dinâmica não Linear , Fenômenos Ópticos , Picratos/química , Treonina/química , Ânions , Cátions , Cristalização , Ligação de Hidrogênio , Conformação Molecular , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Espectroscopia de Luz Próxima ao Infravermelho
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