Interfacial Engineering of Quantum Dots-Metal-Organic Framework Composite Toward Efficient Charge Transport for a Short-Wave Infrared Photodetector

Short-wave infrared (SWIR) quantum dot (QD)-converted photodetectors are one of the promising devices used in artificial intelligence and automatic navigation systems. However, compared to semi-conductor-type photodetectors, they suffer from poor chemical stability and weak electronic conductivity. In this study, a PbS QD and conductive metal-organic framework (MOF) hybrid composite is designed with SWIR detection capability. The Fourier-transform infrared spectroscopy confirms the surface modification of PbS QDs with MOF. X-ray absorption near-edge structures spectra reveal the chemical bonding between MOF and PbS QDs. Furthermore, 2D grazing-incidence small- and wide-angle X-ray scattering is utilized to unveil the particle stacking and the preferred orientation of the PbS@MOF thin film. By integrating the PbS@MOF thin film directly on top of the graphene field effect transistor (FET) device, the chemical stability and photoelectric properties of graphene FET are enhanced, and these are investigated using a focus ion beam with a high-resolution transmission electron microscope. This study offers a strategy to simultaneously improve the chemical stability and the photoelectronic properties of the nanomaterials as well as contribute to the advancement of a QD-converted SWIR photodetector. A PbS quantum dot (QD) and conductive metal-organic framework (MOF) hybrid composite is designed with short-wave infrared (SWIR) detection capability with the chemical bonding between MOF and PbS QDs. By integrating the PbS@MOF thin film directly on top of the graphene field effect transistor device, a highly stable and efficient charge transport SWIR photodetector can be achieved.image