State Key Laboratory Breeding Base of Photocatalysis

Fuzhou, China

State Key Laboratory Breeding Base of Photocatalysis

Fuzhou, China
SEARCH FILTERS
Time filter
Source Type

Zang L.-L.,Fuzhou University | Hu J.-M.,Fuzhou Command Academy | Sun Y.,Fuzhou University | Jin H.,Fuzhou University | And 6 more authors.
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2011

Periodic density functional theory calculations using pseudopotential plane-waves were performed systematically to investigate the surface relaxation of different Al2O3 surfaces including α-Al2O3 (0001) and γ-Al2O3 (110), (110C), and (110D) surfaces, as well as the adsorption of CO molecules on these surfaces. Our calculated results indicate that the CO molecules tend to adsorb perpendicularly on the Al atoms at the surface through carbon atoms and interactions were observed between the CO 5σ state and the substrate. After adsorption, some electrons transferred from the CO molecules to the surface and accordingly the surface work functions of the different Al2O3 surfaces decreased. The adsorption results in small perturbations of the C - O bond length and the corresponding C - O stretching frequency was blue-shifted in all the adsorption structures. By examining the results of the CO adsorption on the different surfaces, it is clear that CO can be used as an effective probe molecule to distinguish the active adsorption sites on the different Al2O3 surfaces. © Editorial office of Acta Physico-Chimica Sinica.


Zhou H.-G.,Fuzhou University | Zhou H.-G.,Yichun University | Wen X.-W.,Fuzhou University | Fang Z.-X.,Fuzhou University | And 5 more authors.
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2013

Density functional theory (DFT) based on the plane wave basis set was used to investigate the geometries, electronic structures, and linear and second-order nonlinear optical properties of a series of AgGa(S1-xSex)2 solid solutions with chalcopyrite structures. The compounds showed similar band structures, and band gaps decreased with increasing x value. When 22.56% Hartree-Fock exchange was employed, the solid solution band gaps predicted by hybrid PBE functionals were consistent with experimental values. The optical properties of AgGa(S1-xSex)2 solid solutions, including refractive index, birefringence, reflectivity, adsorption coefficient, and second harmonic generation coefficient, changed regularly with composition. The range of variation was between that for AgGaS2 and AgGaSe2. The results indicated that crystals with specialized optical performances could be designed. © Editorial office of Acta Physico-Chimica Sinica.


Wu R.-Z.,Fuzhou University | Fang Z.-X.,Fuzhou University | Liu P.,Fuzhou University | Cao Q.-Z.,Fuzhou University | And 7 more authors.
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2013

The electronic structures and optical properties of 4-N,N-dimethylamino-4′ -N′ -methylstilbazolium tosylate (DAST) and 4-N,N-dimethylamino-4′-N′-methylstilbazolium 2,4,6- trimethylbenzenesulfonate (DSTMS) were investigated using density functional theory based on the plane wave basis set. The results indicated that the two compounds showed similar band structures, and the top of the valence band and the bottom of the conductive band mainly originated from the N 2p states of dimethylamino and methylpyridine, respectively. In terms of the linear optical properties, the birefringence indexes, Δn, of the two compounds were very large (Δn>0.5), and they exhibited good light transmission in the mid- and far-infrared regions. With regard to second-order nonlinear optical characteristics, the DAST and DSTMS crystals showed strong second harmonic generation (SHG) responses, and the corresponding SHG coefficients (d11) were about 150 pm·V-1. Analysis of the band structures showed that the SHG responses of the two compounds were closely related to charge transfers between electron-donating and electron-withdrawing groups. Ethylene bridging also played an important role in the charge transfer process. © Editorial office of Acta Physico-Chimica Sinica.


Zhou H.-G.,Fuzhou University | Chen H.,Fuzhou University | Chen D.,Fuzhou University | Li Y.,Fuzhou University | And 5 more authors.
Wuli Huaxue Xuebao/ Acta Physico - Chimica Sinica | Year: 2011

Density functional theory (DFT) based on the pseudo-potential plane wave basis set was used to investigate the electronic structures and optical properties of CuAlX2 (X=S, Se, Te) crystals with a chalcopyrite structure. The results indicate that these compounds have a similar band structure and the bandgap decreases from S to Te. Except for the static birefringence, which is just opposite to a change in the bandgap, the static dielectric constant, refractive index and second harmonic generation (SHG) coefficient d36 of this series of compounds increased from S to Te. The SHG response of the three semiconductors can be attributed to transitions from the occupied bands near the top of the valence band to the unoccupied bands that are contributed to by the p states of the Al and X atoms. Among the three crystals, the optical properties of the CuAlTe2 crystal are better than those of CuAlS2 and CuAlSe2 crystals except that the corresponding static birefringence is too small. © Editorial office of Acta Physico-Chimica Sinica.

Loading State Key Laboratory Breeding Base of Photocatalysis collaborators
Loading State Key Laboratory Breeding Base of Photocatalysis collaborators