Hydrothermal synthesis of nanoporous lead selenide thin films: photoelectrochemical and resistive switching memory applications

Abstract

The interconnected nanoporous lead selenide (PbSe) thin films were synthesized with the aid of polyvinyl alcohol (PVA) as a surface directing agent by simple hydrothermal route. Films were deposited with different time intervals like 1, 2 and 3 h. Effect of time variation was studied by structural, morphological and optical characterizations. XRD analysis revealed that the film exhibit a cubic phase of PbSe. SEM study shows an evolution in nanoflakes like morphological feature. It is observed that, the nanoflakes become denser with an increase in the diameter of the platelets as the deposition time increases. Interconnected nanoporous network, forming well defined 3D nanoenvelopes has been developed to analyze solar cell and resistive switching properties. The photoelectrochemical (PEC) performance of nanoporous PbSe thin films was tested in Polysulfide electrolyte. Among all PbSe films, the sample prepared at 3 h shows higher PEC performance with maximum short circuit current 97 µA/cm2 and open circuit voltage 110 mV. In addition to this, Ag/PbSe/FTO thin film device shows the photo-induced resistive switching behavior. The non-volatile memory results suggested that the memory device is able to switch up to 104 cycles and store the data up to 103 s with good uniformity during the resistive switching process. The analysis of I–V results revealed that the Ohmic and space-charge-limited current are responsible for current conduction in the Ag/PbSe/FTO thin film memory device. The results of present investigation suggest that the nanoporous lead selenide thin films are potential candidate for the photoelectrochemical and resistive switching memory applications.