Epitaxial Growth of 1D Atomic Chain Based Se Nanoplates on Monolayer ReS₂ for High-Performance Photodetectors

Mixed-dimensional (0D, 1D, and 3D) heterostructures based on 2D layered materials have been proven as a promising candidate for future nanoelectronics and optoelectronics applications. In this work, it is demonstrated that 1D atomic chain based Se nanoplates (NPs) can be epitaxially grown on monolayer ReS₂ by a chemical transport reaction, thereby creating an interesting mixed-dimensional Se/ReS₂ heterostructure. A unique epitaxial relationship is observed with the (110) planes of the Se NPs parallel to the corresponding ReS₂ (010) planes. Experimental and theoretical studies reveal that the Se NPs could conjugate with underlying monolayer ReS₂ via strong chemical hybridization at heterointerface, which is expected to originate from the intrinsic defects of ReS₂. Remarkably, photodetectors based on Se/ReS₂ heterostructures exhibit ultrahigh detectivity of up to 8 × 10¹² Jones, and also show a fast response time of less than 10 ms. These results illustrate the great advantage of directly integrated 1D Se based nanostructure on planar semiconducting ReS₂ films for optoelectronic applications. It opens up a feasible way to obtain mixed-dimensional heterostructures with atomic interfacial contact by epitaxial growth.