Fabrication of a Semiconducting Supramolecular Nickel(II)-Based Metallogel as an Efficient Active Material for Nonvolatile Memory Applications

A supramolecular Ni(II)-based metallogel, denoted as Ni@3AP, has been developed using 3-amino-1-propanol (3AP) in an aqueous medium. The mechanical behavior of the Ni@3AP metallogel was systematically estimated through rheological measurements, including frequency-dependent analysis and thixotropic recovery studies. This metallogel has a well-defined, rod-like, interconnected network, which is observed from FESEM images, and we confirmed the elemental conformation of this metallogel from energy-dispersive X-ray (EDX) mapping. The coordination-driven gelation mechanism was further investigated using Fourier transform infrared (FTIR) spectroscopy. To explore its charge transport properties, a Ni@3AP metallogel-based planar device was fabricated with a metal−semiconductor−metal configuration. Moreover, Ni@3AP metallogel-based resistive random-access memory (RRAM) devices were designed, which exhibited a reliable bipolar resistive switching behavior, with an ON/OFF current ratio of approximately 120 up to 5000 switching cycles. Further, using the Ni@3AP metallogel-based RRAM device, a 2 × 2 crossbar array was developed to explore their logical operation. These results highlight the potential of this metallogel system for applications in in-memory and neuromorphic computing.