Optimization of Ag2S Quantum Dots Decorated ZnO Nanorod Array Photoanodes for Enhanced Photoelectrochemical Performances

Solis-Cortes, Daniel; Martin Jimenez, Francisco; Jauregui, Guillermo; Gau, Daniel; Pereyra, Javier; Henriquez, Rodrigo; Marotti, Ricardo E.; Ramon Ramos-Barrado, Jose; Dalchiele, Enrique A

Abstract

The synthesis of Ag2S quantum dots (QDs) deposited on the surface of electrodeposited ZnO nanorods (NRs) by a successive ionic-layer adsorption and reaction (SILAR) method is reported. A Box-Behnken response surface factorial design was used to organize the experiments conducted and identify the effects of three electrochemical parameters and their potential interactions. These parameters include zinc precursor concentration in the electrolytic bath, the electrolytic bath temperature and the electrodeposition time on the morphological and structural properties of the electrochemically grown ZnO nanorods. Morphological, structural and optical characterizations of these NRs heterojunctions were done. A direct band gap for Ag2S QDs, tuned between 2.54 and 2.73 eV by varying the SILAR cycle numbers, was determined. The presence of ZnO nanostructures increases the light scattering capability of the samples, allowing an important quantity of diffuse light near the absorption edge of Ag2S. The photoelectrochemical performance of these ZnO NRs decorated with Ag2S QDs based photoanodes has been evaluated. The SILAR parameters related to the growth of the Ag2S QDs that optimize the performance of this photoelectrode are presented. The effect of a ZnS passivation layer has been studied leading to an increase of about 400% in the short-circuit current density after passivation.

Más información

Título según WOS: Optimization of Ag2S Quantum Dots Decorated ZnO Nanorod Array Photoanodes for Enhanced Photoelectrochemical Performances
Título de la Revista: JOURNAL OF THE ELECTROCHEMICAL SOCIETY
Volumen: 168
Número: 5
Editorial: ELECTROCHEMICAL SOC INC
Fecha de publicación: 2021
DOI:

10.1149/1945-7111/AC001A

Notas: ISI