Extended photocurrent performance of antimony trisulfide/reduced graphene oxide composite prepared via a facile hot-injection route

Antimony trisulfide/reduced graphene oxide (Sb2S3-rGO) composite was successfully prepared via a facile hot-injection route at a relatively low temperature using ethylene glycol (EG) as a nontoxic and cost-effective solvent. The phase, structure, and characteristic properties of the products were examined by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDS), and UV-vis spectroscopy. The results revealed that growth of Sb2S3 nanorods on rGO occurred with a single phase and average diameter of 50 nm. An optimum temperature of 150 degrees C was confirmed for the synthesis of Sb2S3-rGO using the hot-injection method. Furthermore, electrochemical impedance spectroscopy (EIS) measurement revealed an excellent reduction in charge transfer resistance (R-CT) of Sb2S3-rGO layer that is about 20 times smaller than that of Sb2S3, indicating an obvious increase in charge transport and reduction in recombination rate. Also, compare to Sb2S3, the transient photocurrent response of Sb2S3-rGO layer was sharply enhanced by a factor of 6 probably because of the excellent electric conductivity of rGO in Sb2S3-rGO composite layer. These results strongly suggest Sb2S3-rGO composite as an earth-abundant compound in solar cell applications.