Gate-Controlled InSe/PtS2 van der Waals Heterostructures for High-Performance Electronic and Optoelectronic Devices

The unique combination of atomically thin layers and well-defined interfaces in two-dimensional (2D) semiconductors holds promise for applications in electronics and optoelectronics. As promising newcomers, p-type InSe and n-type PtS₂ nanosheets present exciting possibilities, with their unique characteristics. Here, we investigate gate-controlled InSe/PtS₂ van der Waals heterostructures (vdWHs), highlighting their potential as candidates for advanced electronic and optoelectronic applications. This work demonstrates the realization of a 2D p-n diode with a precisely defined atomic interface, exhibiting strong interlayer interactions. InSe/PtS₂ vdWHs demonstrate impressive functionalities surpassing previously reported van der Waals counterparts with gate-dependent rectification of 1.5 × 10⁵ at a gate voltage of V_g = −20 V and ideality factor of 1.17, close to an ideal diode. Investigating the photovoltaic response of the InSe/PtS₂ heterostructure under varied light intensities revealed a significant responsivity that varies from 31.85 to 43.2 A/W upon exposure to a light wavelength of 220 nm. Additionally, a substantial external quantum efficiency (EQE) ratio of ∼2.4 × 10⁴ % with high detectivity (D*) of 7.06 × 10⁹ Jones values is achieved. This work demonstrates the development of advanced p-n junctions, paving the way for the realization of high-performance electronics and optoelectronic devices.