Quasiepitaxy Strategy for Efficient Full‐Inorganic Sb₂S₃ Solar Cells

Abstract

Antimony sulfide (Sb2S3) as a wide‐bandgap, nontoxic, and stable photovoltaic material reveals great potential for the uppermost cells in Si‐based tandem cell stacks. Sb2S3 solar cells with a compatible process, acceptable cost, and high efficiency therefore become the mandatory prerequisites to match silicon bottom cells. The performance of vacuum processed Sb2S3 device is pinned by bulk and interfacial recombination. Herein, a thermally treated TiO2 buffer layer induces quasiepitaxial growth of vertical orientation Sb2S3 absorber overcoming interface defects and absorber transport loss. Such novel growth could pronouncedly improve the open‐circuit voltage (Voc) due to the superior interface quality and intraribbon transport. The epitaxial rough Sb2S3 surface shows a texturized‐like morphology. It is optimized by tuning the grain sizes to form strong light trapping effect, which further enhances the short‐circuit current density (Jsc) with a 16% improvement. The final optimal device with high stability obtains a power conversion efficiency of 5.4%, which is the best efficiency for full‐inorganic Sb2S3 solar cells. The present developed quasiepitaxy strategy supports a superior interface, vertical orientation, and surface light trapping effect, which provides a new perspective for efficient noncubic material thin film solar cells.

In Situ Growth of [hk1]‐Oriented Sb2S3 for Solution‐Processed Planar Heterojunction Solar Cell with 6.4% Efficiency

“…Further, until very recently, only one study investigated the effect of Sb 2 S 3 orientation on device performance, in which the Sb 2 S 3 film was fabricated by RTP process followed by selenium treatment, delivering a PCE of 5.4%. [19] However, there is still no report on selective growth of [hk1]-oriented Sb 2 S 3 by mainstream solution methods.…”

High Open‐Circuit Voltage in Full‐Inorganic Sb2S3 Solar Cell via Modified Zn‐Doped TiO2 Electron Transport Layer

“…[ 16 ] Recently, the encouraging results of Cd‐free buffer layers such as SnO 2, [ 17 ] ZnO, [ 18 ] and TiO 2 [ 19 ] pave further research to overcome this inadequacy, where TiO 2 as ETL has been well‐intentioned by promoting the epitaxial growth mechanism for Sb 2 S 3 films. [ 4 ]…”

Crystallographic Orientation Control of 1D Sb2Se3 Nanorod Arrays for Photovoltaic Application by In Situ Back‐Contact Engineering

“…Once the interfacial bonding formed, the anisotropic surface energy of orthorhombic Sb 2 Se 3 determines the (Sb 4 Se 6 ) n ribbons extend to [001] direction. [ 2,5,7,20 ] In this case, the growth process might be in an island‐like formation mode (Volmer–Weber mode), [ 21 ] as shown in Figure 2j, where the reached Se, Sb, and Sb–Se species could diffuse and absorbed by these stable nuclei, and the nuclei grow to Sb 2 Se 3 crystalline seeds that maintain their original orientations. Then, according to the calculation results, the surfaces parallel to the c ‐axes: (100), (010), (110), and (120), have lower surface energies than the (001), (211), and (221) surfaces.…”