Colloidal bismuth sulfide nanoparticles: a photoelectrochemical study of the relationship between bandgap and particle size

Abstract

A method of preparing Bi₂S₃ nanoparticles by arrested precipitation is described. It is shown that varying the amount of stabiliser employed in the preparation controls the size of the particles. The as-prepared nanoparticles may be self-assembled on a tin oxide substrate. Photocurrent studies of the Bi₂S₃ modified electrode indicate that the presence of an oxidisable surface trap at approximately −0.15 V vs. Ag|AgCl|3.0 mol dm⁻³ NaCl. Photocurrent spectra indicate that the band edge of the Bi₂S₃ particles is only weakly dependent on particle size, consistent with a high effective mass of electrons in this material.