Nanorod array-induced growth of high-quality Sb2Se3 absorber layers for efficient planar solar cells

Antimony selenide (Sb ₂Se ₃) has been applied extensively in the field of optoelectronics because of its excellent material and photoelectric properties, as well as its potential low cost effectiveness. Owing to its unique quasi-one-dimensional structure, the preparation of an Sb ₂Se ₃ absorption layer with high crystallization quality and standing preferred orientation is crucial for constructing high-performance Sb ₂Se ₃ devices. Herein, we reported a new method for the subsequent epitaxial growths of Sb ₂Se ₃ thin films with high crystallization and preferred standing orientations using the Sb ₂Se ₃ nanorod array as growth template on the Mo substrate and summarized the growth mechanism of the nanorod arrays. High crystal quality and crystal orientation can be easily controlled, carrier recombination is reduced, charge transport is enhanced, and the performance of Sb ₂Se ₃ device is improved significantly. As high as 6.3 % power-to-efficiency with a fill factor of 62 % has been achieved for the champion device. This general-purpose nanorod array template growth film provides an effective reference for the growth control of other low latitude crystal films.