Filmes de ZnO e ZnO dopado com nitrogênio: efeito do processo de dopagem nas propriedades e atividade fotocatálica para a degradação de rodamina b

Abstract

ZnO is an n type semic onductor oxide that has stood out for its properties that enable applications in various areas and is promising for heterogeneous photocatalysis. In the present study, we investigated the structural, morphological, photoelectrochemical and photocatalytic p roperties of ZnO and ZnO films prepared in the presence of N 2 in fluorinated doped tin oxide (FTO) conductive glass and N 2 bubbling for doped films. fluorine. Time conditions, N 2 flux and calcination temperature were investigated. X ray diffraction pattern s have shown that ZnO and ZnO: N films have a wurtzite structure. Values of 3.25 3.27 eV of gap energy of the films were estimated by the Tauc method from the UV vis curves. FE SEM images showed a change in the morphology of the ZnO film obtained in th e presence of N 2 . Photoelectrochemical studies showed a higher photocurrent density for ZnO and ZnO:N films using a 20 cm 3 min 1 flux calcined at 500 ° C with ca. 48 and 70 µA cm 2 (0.7 V vs. Ag/AgCl), respectively. ZnO and ZnO: N electrodes (20 cm 3 min 1 were used to degrade an aqueous 0.48 mg L 1 RhB dye solution under polychromatic irradiation for 165 min. The degradation study was investigated under heterogeneous photocatalysis (FH) and electrochemically assisted FH (FHE) photocatalysis conditions. For the photobleaching of the RhB dye, the obtained performances were 19% and 36% in FH for ZnO and ZnO: N, respectively. And for the FHE configuration with application of a potential of +0.7 V vs Ag/AgCl, the values were 26% and 43% for ZnO and ZnO:N, resp ectively. The studies presented here reveal that N doped ZnO films are promising as photoanodes for photoelectrocatalysis applications.