Transferable Highly (001) Oriented Sb₂Se₃ Nanorod Films on Flexible Substrates for Innovative Optoelectronic Devices

Abstract Thin films of antimony chalcogenides, Sb₂X₃ (X = S, Se, or S_xSe_1−x), comprised of (001) oriented nanorods are highly desirable for optoelectronic applications owing to their light trapping capacity and highly efficient charge transport along the optimally aligned quasi‐1D (Sb₄X₆)_n ribbons. Here, highly (001) oriented Sb₂Se₃ nanorod (Sb₂Se₃NR) layers are obtained via a novel template growth method, and transfer these layers to functional substrates via a polymer‐assisted technique. Transferable layers overcome the current challenges associated with achieving oriented growth directly on the desired substrate. Using a combination of a low‐temperature processable SnO₂ nanoparticle transport layer and encapsulation/etching techniques photodetector devices are fabricated with excellent electrical contact. The optimized transferred devices show broad range photoresponse with signal‐to‐noise ratios up to 10⁵ and responsivities reaching 0.96 mA W⁻¹. Importantly, access to low‐temperature processing enables the fabrication of flexible devices. Based on this platform, a proof‐of‐concept self‐powered flexible heart rate monitor is fabricated. The achievement of transferable Sb₂Se₃NR layers introduced in this work is expected to be readily applicable to generate new (001) Sb₂Se₃ device architectures that may otherwise not be achievable via direct deposition, with application in photoelectrochemical water splitting, battery electrodes, and solar cells.