A semiconducting supramolecular Co(II)-metallogel based resistive random access memory (RRAM) design with good endurance capabilities

Arpita Roy; Subhendu Dhibar; Saurav Kumar; Kripasindhu Karmakar; Parul Garg; Pradip Ruidas; Subham Bhattacharjee; Ashok Bera; Bidyut Saha; Soumya Jyoti Ray

doi:10.1038/s41598-024-74994-1

A semiconducting supramolecular Co(II)-metallogel based resistive random access memory (RRAM) design with good endurance capabilities

Sci Rep. 2024 Nov 6;14(1):26848. doi: 10.1038/s41598-024-74994-1.

Authors

Affiliations

¹ Department of Physics, Indian Institute of Technology Patna, Bihar, 801106, India.
² Colloid Chemistry Laboratory, Department of Chemistry, The University of Burdwan, Golapbag, Burdwan, 713104, West Bengal, India. [email protected].
³ Colloid Chemistry Laboratory, Department of Chemistry, The University of Burdwan, Golapbag, Burdwan, 713104, West Bengal, India.
⁴ Department of Physics, Indian Institute of Technology, Jammu, J&K-181221, India.
⁵ Department of Chemistry, Kazi Nazrul University, Asansol, 713303, West Bengal, India.
⁶ Colloid Chemistry Laboratory, Department of Chemistry, The University of Burdwan, Golapbag, Burdwan, 713104, West Bengal, India. [email protected].
⁷ Department of Physics, Indian Institute of Technology Patna, Bihar, 801106, India. [email protected].

Abstract

A highly efficient approach for synthesizing a supramolecular metallogel of Co(II) ions, denoted as CoA-TA, has been established under room temperature and atmospheric pressure conditions. This method employs the metal-coordinating organic ligand benzene-1,3,5-tricarboxylic acid as a low molecular weight gelator (LMWG) in DMF solvent. A comprehensive analysis of the mechanical properties of the resulting supramolecular Co(II)-metallogel was conducted through rheological investigation, considering angular frequency and thixotropic study. The hierarchical rocky network structure of the supramolecular Co(II)-metallogel was unveiled using field emission scanning electron microscopy (FESEM). Transmission electron microscopic (TEM) analysis showed rod-shaped structures via low-magnification high angle annular dark field (HAADF) bright field scanning transmission electron microscopic (STEM) imaging, while energy dispersive X-ray (EDX) elemental mapping confirmed its primary chemical constituents. The formation mechanism of the metallogel was examined via fourier transform infrared spectroscopy (FTIR) spectroscopy. The nature of the synthesized CoA-TA metallogel was affirmed through powder X-ray diffraction (PXRD) analysis. Furthermore, this study involved fabrication of Schottky diode structures in a metal-semiconductor-metal geometry based on cobalt(II) metallogel (CoA-TA), enabling observation of charge transport behavior. Remarkably, a resistive random access memory (RRAM) device utilizing cobalt(II) metallohydrogel (CoA-TA) demonstrated bipolar resistive switching at room temperature and under ambient conditions. The switching mechanism was investigated, revealing the formation and rupture of conductive filaments between metal electrodes that govern the resistive switching behavior. This RRAM device exhibited an impressive ON/OFF ratio (~ 414) and exceptional endurance over 5000 switching cycles. These structures offer great potential for diverse applications such as non-volatile memory design, neuromorphic computing, flexible electronics and optoelectronics. Their advantages lie in their fabrication process, reliable resistive switching behavior and overall performance stability.

Keywords: Cross-bar array; Electronic device; In-memory computing; Microstructure; Neuromorphic computing; Non-volatile memory; Resistive random access memory device; Rheology; Supramolecular Cobalt(II) Metallogel.