Thermally induced structural evolution and performance of Sb2Se3 films and nanorods prepared by an easy sputtering method

- Thermally induced mechanism of Sb2Se3 film and nano-rod prepared by sputtering.
- Tsub is the key for Sb2Se3 films and an efficient self-organization for nano-rods.
- High crystalline Sb2Se3 film prepared at 325 °C, 3.35% PCE in solar cell achieved.

An easy method of preparing well-crystallized Sb2Se3 films and nanorods through magnetron sputtering was proposed, and their growth mechanism was examined. The microstructure, morphology, composition, and optical and electrical properties of the Sb2Se3 films depended strongly on the substrate temperature (Tsub). Sb2Se3 films prepared at > 250 °C contained the orthorhombic phase without Sb2O3 phase owing to the high-purity vacuum environment. Well-crystallized Sb2Se3 films deposited at Tsub = 325 °C showed compact grains with a bandgap of 1.23 eV and a high absorption coefficient of 105 cm−1 in the visible region. Photoelectrochemical measurements showed that Sb2Se3 films were p-type semiconductors with excellent photoresponse. A clear photovoltaic effect with a power conversion efficiency (PCE) of 3.35% was measured for the first time by using the sputtering Sb2Se3 films as absorbers in a photovoltaic solar cell. At Tsub = 375 °C, highly uniform films with monodispersed Sb2Se3 nanorods were obtained. The preferential orientation of the Sb2Se3 crystals by self-organization was promoted by increasing Tsub. By using the Sb2Se3 nanorods as absorbers in a solar cell, good photoresponse and a PCE of 2.15% were achieved.