Gate-Controlled\nInSe/PtS<sub>2</sub> van der Waals\nHeterostructures for High-Performance Electronic and Optoelectronic\nDevices

The unique combination of atomically thin layers and\nwell-defined\ninterfaces in two-dimensional (2D) semiconductors holds promise for\napplications in electronics and optoelectronics. As promising newcomers,\np-type InSe and n-type PtS<sub>2</sub> nanosheets present exciting\npossibilities, with their unique characteristics. Here, we investigate\n gate-controlled InSe/PtS<sub>2</sub> van der Waals heterostructures\n(vdWHs), highlighting their potential as candidates for advanced electronic\nand optoelectronic applications. This work demonstrates the realization\nof a 2D p-n diode with a precisely defined atomic interface, exhibiting\nstrong interlayer interactions. InSe/PtS<sub>2</sub> vdWHs demonstrate\nimpressive functionalities surpassing previously reported van der\nWaals counterparts with gate-dependent rectification of 1.5 ×\n10<sup>5</sup> at a gate voltage of <i>V</i><sub>g</sub> = −20 V and ideality factor of 1.17, close to an ideal diode.\nInvestigating the photovoltaic response of the InSe/PtS<sub>2</sub> heterostructure under varied light intensities revealed a significant\nresponsivity that varies from 31.85 to 43.2 A/W upon exposure to a\nlight wavelength of 220 nm. Additionally, a substantial external quantum\nefficiency (EQE) ratio of ∼2.4 × 10<sup>4</sup> % with\nhigh detectivity (<i>D</i>*) of 7.06 × 10<sup>9</sup> Jones values is achieved. This work demonstrates the development\nof advanced p-n junctions, paving the way for the realization of high-performance\nelectronics and optoelectronic devices.