In Situ Growth Of [Hk1]-Oriented Sb(2)S(3)For Solution-Processed Planar Heterojunction Solar Cell With 6.4% Efficiency

Binary compound antimony sulfide (Sb2S3) with its nontoxic and earth-abundant constituents, is a promising light-harvesting material for stable and high efficiency thin film photovoltaics. The intrinsic quasi-1D (Q1D) crystal structure of Sb(2)S(3)is known to transfer photogenerated carriers rapidly along the [hk1] orientation. However, producing Sb(2)S(3)devices with precise control of [hk1] orientation is challenging and unfavorable crystal orientations of Sb(2)S(3)result in severe interface and bulk recombination losses. Herein, in situ vertical growth of Sb(2)S(3)on top of ultrathin TiO2/CdS as the electron transport layer (ETL) by a solution method is demonstrated. The planar heterojunction solar cell using [hk1]-oriented Sb(2)S(3)achieves a power conversion efficiency of 6.4%, performing at almost 20% higher than devices based on a [hk0]-oriented absorber. This work opens up new prospects for pursuing high-performance Sb(2)S(3)thin film solar cells by tailoring the crystal orientation.