Controlled Growth of Large-Area 2d Palladium Diselenide with Tunable Electronic Properties for Optoelectronics and Artificial Synapses Devices

Abstract

Two-dimensional palladium selenide (2D PdSe2) exhibits exceptional potential for optoelectronic and artificial synaptic devices due to its high electron mobility, tunable band gap, and remarkable air stability. Here, a liquid-phase precursor-assisted chemical vapor deposition (CVD) method is presented for the growth of large-area 2D PdSe2 films using immobilized precursors. This approach enables precise control over precursor concentration and spin-coating rates, allowing for the production of uniform films with varying thicknesses and facilitating the modulation of electrical properties, such as bandgap and work function. Arrayed field-effect transistors (FETs) based on as-grown 2D PdSe2 films exhibit intrinsic bipolar characteristics, with maximum electron mobilities of 30 cm2 V−1 s−1 and notable on/off ratios. Additionally, the 2D PdSe2-based photodetectors exhibit impressive responsivity and detectivity. Importantly, the arrayed artificial synaptic devices demonstrate excellent conductance linearity and achieve up to 83.26% accuracy in handwritten digit recognition, highlighting the material's promise for flexible electronic applications.

Keywords: PdSe2, CVD growth, Tunable electronic properties, Photodetectors, Artificial synaptic devices