Unipolar resistive switching behaviour of copper doped polyvinyl alcohol/lead sulphide quantum dot device

Copper doped lead sulphide quantum dots (PVA/PbS:Cu) with 0.5 and 1 % Cu dopant concentration were synthesized by chemical route. Structural, chemical and optical characterizations viz., X-ray diffraction study, UV-visible spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, selected area electron diffraction were done to confirm nanoformation in the as-synthesized copper doped lead sulphide samples. Significant changes in structural, optical and electrical properties of the as-fabricated samples were observed with variation in percentage of copper dopant concentration. I-V characteristics of the as-fabricated AL/PVA/PbS:Cu QD/ITO devices with the PVA/PbS:Cu samples as the active layer of the devices, exhibits unipolar resistive switching characteristics with R-OFF/R-ON ratio of similar to 10(2) and similar to 10(3). Variation in the R-OFF/R-ON ratios of investigated devices with different copper dopant concentrations points towards possibility of designing AL/PVA/PbS:Cu QD/ITO devices with different R-OFF/R-ON ratios by varying Cu dopant concentration.