Abstract
Antimony selenide (Sb(2) Se(3) ) nanorod arrays along the [001] orientation are known to transfer photogenerated carriers rapidly due to the strongly anisotropic one-dimensional crystal structure. With advanced light-trapping structures, the Sb(2) Se(3) nanorod array-based solar cells have excellent broad spectral response properties, and higher short-circuit current density than the conventional planar structured thin film solar cells. However, the interface engineering for the Sb(2) Se(3) nanorod array-based solar cell is more crucial to increase the performance, because it is challenging to coat a compact buffer layer with perfect coverage to form a uniform heterojunction interface due to its large surface area and length-diameter ratio. In this work, an intermeshing In(2) S(3) nanosheet-CdS composite as the buffer layer, compactly coating on the Sb(2) Se(3) nanorod surface is constructed. The application of In(2) S(3) -CdS composite buffers build a gradient conduction band energy configuration in the Sb(2) Se(3) /buffer heterojunction interface, which reduces the interface recombination and enhances the transfer and collection of photogenerated electrons. The energy-level regulation minimizes the open-circuit voltage deficit at the interfaces of buffer/Sb(2) Se(3) and buffer/ZnO layers in the Sb(2) Se(3) solar cells. Consequently, the Sb(2) Se(3) nanorod array solar cell based on In(2) S(3) -CdS composite buffers achieves an efficiency of as high as 9.19% with a V(OC) of 461 mV.