Enhanced light absorption in high-quality three-dimensional Sb2S3 micropillar arrays based on template-assisted growth

Abstract

Sb2S3 has garnered significant attention in photovoltaic applications due to its suitable bandgap, single stable orthogonal phase and excellent stability. However, due to the coexistence of indirect transition parts in the bandgap, a thicker Sb2S3 absorption layer is usually required to achieve decent light absorption in solar cells, which inevitably leads to an increase in trapped states in the bulk. Therefore, it is of great importance to realize more photogenerated carriers without increasing charge recombination. Here, we realized the in-situ growth of high-quality Sb2S3 micropillar arrays on the template prepared by laser direct writing. Compared with the traditional thick layer, this array structure with less material usage can not only achieve more light absorption by enhancing photon scattering, but also optimize carrier transport at the interface by expanding their contact area with the hole transporting layer. This work provides a strategy for controllably achieving enhanced light absorption of Sb2S3 structures, which is a perspective for the improvement of highly efficient solar cells.