Resistive switching properties of CdTe/CdSe core–shell quantum dots incorporated organic cow milk for memory application

Our study focuses on the resistive switching memory characteristics of devices containing active layers of CdTe/CdSe core–shell quantum dots (QDs) dispersed in organic cow milk. We fabricated devices containing CdTe/CdSe particles per volume of milk using a direct-dipping method, with particle concentrations of 2.4 × 10⁻⁵ (S1), 4.8 × 10⁻⁵ (S2), and 7.2 × 10⁻⁵ (S3). This method was cost-free. Distinct memory characteristics were observed among devices featuring these concentrations. S1- and S2-based devices exhibited memory behavior with ‘S-type’ and ‘O-type’ hysteresis, respectively. The device based on S3 exhibited an initial asymmetric ‘N-type’ behavior with a large ON/OFF ratio (≥10⁴). The memory attribute of the aforementioned device disappeared after the initial three cycles but was subsequently restored by modifying the scan voltage step from 10 mV to 1 mV. The observed results indicate typical symmetric ‘N-type’ behavior of the device, accompanied by threshold switching under positive voltage bias. Additionally, the switching was observed to be as low as 0.04 V. The S1- and S2-based devices were found to exhibit hopping conduction and Schottky emission in the OFF- and ON-state, respectively, while the S3-based device showed conductive bridge resistive switching as the conduction mechanism. The findings indicate that it is possible to produce biodegradable and disposable memory devices using full cream cow milk and CdTe/CdSe core–shell QDs. The device’s switching and memory functions can be manipulated by regulating the quantity of CdTe/CdSe particles present in the milk. Finally, we have demonstrated that the switching behavior of ReRAMs based on milk can be influenced by the voltage steps used during scanning.