RESUMO
BaTiO3/Cu2O and BaTiO3/Cu2O/Au complexes were prepared from CuCl2, HAuCl4 solution, and BaTiO3 by the solution method. BaTiO3 particles were dispersed in a CuCl2 solution, and the BaTiO3/CuO complex was produced through crystallization of CuO onto the BaTiO3 surface by hydrolysis of CuCl2 in the first stage. After the reaction, CuO was reduced to Cu2O by treatment with glucose, thereby yielding the BaTiO3/Cu2O complex. The BaTiO3/Cu2O/Au complex was prepared by treating the BaTiO3/Cu2O particles with HAuCl4. Under visible light, the obtained BaTiO3/Cu2O0/Au complex showed higher photocatalytic activity than the Degussa P-25sample. In addition, the BaTiO3/Cu2O complex showed excellent antipathogenic effect.
Assuntos
Aspergillus nidulans/efeitos dos fármacos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Fotoquímica/métodos , Antifúngicos/administração & dosagem , Antifúngicos/síntese química , Aspergillus nidulans/crescimento & desenvolvimento , Compostos de Bário/administração & dosagem , Compostos de Bário/química , Compostos de Bário/efeitos da radiação , Catálise/efeitos da radiação , Sobrevivência Celular/efeitos dos fármacos , Cobre/administração & dosagem , Cobre/química , Cobre/efeitos da radiação , Relação Dose-Resposta a Droga , Ouro/administração & dosagem , Ouro/química , Ouro/efeitos da radiação , Luz , Teste de Materiais , Nanopartículas Metálicas/efeitos da radiação , Titânio/administração & dosagem , Titânio/química , Titânio/efeitos da radiaçãoRESUMO
In marokite CaMn(2)O(4), all six Mn-O bonds of each MnO(6) octahedron are different because of the Jahn-Teller distortion so that every Mn(3+) (d(4)) ion has six different superexchange interactions with its neighboring Mn(3+) ions. The spin exchange interactions of CaMn(2)O(4) were examined on the basis of spin dimer analysis to find what geometrical parameters of the Mn-O-Mn superexchange paths control the signs and strengths of their spin exchange interactions. Our work correctly describes the magnetic structure of CaMn(2)O(4) observed from neutron powder diffraction measurements and shows that the antiferromagnetic interactions of the Mn-O-Mn paths depend primarily on the asymmetry and the Mn-O bond length of the Mn-O-Mn bridge, but not on the 90 degree angle Mn-O-Mn bond angle.
