Mixed-Dimensional 0D-DNA-2D Heterostructures Beyond van der Waals: A DNA-Templated Strategy for Optoelectronic Tunability

Abstract

The assembly of nanomaterials of different dimensionality into mixed-dimensional heterostructures can allow circumventing individual nanomaterials intrinsic limitations toward the development of novel hybrids for a variety of technological applications. Critical to this end is the ability to control the interface of the single components in terms of spatial separation and chemical nature, in order to optimize their synergistic coupling, tailor their optoelectronic properties, and potentially impart novel functionalities. Herein the controlled assembly and optoelectronic tunability of 0D-2D heterostructures is demonstrated, employing DNA as a linking and template moiety for the modular assembly of metal sulfide nanoparticles (NPs) on MoS₂, with nanoscale control over their separation and ability to concomitantly assemble different kind of NPs on the same DNA template linker. The developed aqueous solution-processable approach permits the systematic modulation of charge carrier doping and trion formation in the transition metal dichalcogenide (TMD) in a non-destructive manner. Moreover, it allowed to tailor the photoinduced electrical response -with ultrahigh detectivity- of NPs-TMD phototransistors to different wavelengths, thanks to the concomitant presence of different nanoparticles by design. These are key requirements for optimal and scalable implementation of low-dimensional materials and their heterostructures in optoelectronic devices.