[hk1]–oriented 1D Sb2S3 nanorod array as high–performance photoanode for solar water splitting

Sluggish charge transport kinetics and significant optical loss are known to severely limit the photoelectrochemical activity of the antimony sulfide (Sb₂S₃) for solar water splitting. Those issue are, however, well addressed in the present contribution via the morphology control and crystallographic texturization, which are simultaneously achieved using the gold–coated fluorine–doped tin oxide (Au@FTO) coated glass substrate as the back contact to Sb₂S₃. As–obtained Sb₂S₃/Au@FTO exhibits a preferred [hk1] orientation to accelerate the charge transport and rod–like nanostructure to scatter the incident light, leading to the optical path length markedly increased. Benefitting from such enhanced light harvesting ability of Sb₂S₃/Au@FTO, numerous photoexcited electron–hole pairs are generated while their recombination loss is substantially quenched by the facile carrier transport kinetics. Their synergistic effect enhances the photocurrent density delivered by Sb₂S₃/Au@FTO, which amounts to ∼2.3 mA cm⁻², far exceeding those deposited on the bare and titanium dioxide–coated FTO substrates, which are additionally prepared as the counterparts of Sb₂S₃/Au@FTO for comparison. More importantly, such superiority is further seen when comparing with those of additional Sb₂S₃–based photoelectrodes reported in the literature, by which is its great promise well corroborated.