Spatially branched CdS–Bi2S3 heteroarchitecture: single step hydrothermal synthesis approach with enhanced field emission performance and highly responsive broadband photodetection

Abstract

This report explores the controlled hierarchical synthesis of CdS nanostructure branches on Bi₂S₃ nanorod cores via a facile single step hydrothermal route. Morphological and structural studies reveal the formation of CdS–Bi₂S₃ heteroarchitecture with excellent stoichiometry between the constituent elements. The growth of CdS over Bi₂S₃ strongly depends on optimization of the reaction conditions, especially low PVP concentration. Furthermore, the as-synthesized CdS–Bi₂S₃ heteroarchitecture demonstrates multifunctionality in field emission and photoresponse. Interestingly, the CdS–Bi₂S₃ heteroarchitecture shows enhanced field emission properties such as low turn-on field (∼1.8 V μm⁻¹ for 10 μA cm²), high emission current density and better current stability in comparison to Bi₂S₃ and other nanostructures. The as-synthesized CdS–Bi₂S₃ heteroarchitecture exhibits considerable response and recovery times, ∼207 ms and 315 ms, respectively in comparison to bare Bi₂S₃ nanostructures (∼655 ms and 678 ms). The present results demonstrate CdS–Bi₂S₃ heteroarchitecture as a potential candidate for future optoelectronic device applications.