Construction of CdS/Sb2Se3 planar heterojunction by full vapor transport deposition

In this work, we develop a vapor transport deposition (VTD) technology to prepare CdS film with tetragonal phase for the first time, and then construct a CdS/Sb2Se3 planar heterojunction by full VTD tactics. Compared with the CdS synthesized by traditional chemical bath deposition (CBD), the CdS-VTD has superior crystalline, conductivity and lower Urbach energy, which also induces the growth orientation of Sb2Se3 and has a favorable energy level matching structure with Sb2Se3. With the improved carrier transport efficiency, finally, the built carbon-based Sb2Se3 device delivers an efficiency of 4.91%, obviously improved by 15.8% than Sb2Se3 device with CdS-CBD (4.24%), which is the champion Sb2Se3 device with full VTD process and pave a successive way for the construction of CdS/Sb2Se3 planar heterojunction.