Design and Evaluation of Dibenzothiophene Sulfone‐Based Donor–Acceptor Architectures for High‐Performance Resistive WORM Memory Devices

In the quest for advanced resistive memory devices, the rational design of π-conjugated small molecules is increasingly recognized as an effective approach to achieving high-performance, non-volatile data storage. Herein, we report the design and synthesis of a series of D-A-D' and D-π-A-π-D' type molecules featuring dibenzothiophene sulfone as the central acceptor, marking its debut application in organic resistive memory device applications. The molecules were unsymmetrically functionalized through the incorporation of different donor units such as tert- butylphenyl, triphenylamine, and methoxyphenyl units. Furthermore, the incorporation of acetylene bridges enhanced π-conjugation and facilitated intramolecular charge transfer. Photophysical and electrochemical studies revealed intramolecular charge-transfer characteristics and band gap values in the range of 3.0-3.8 eV. All fabricated devices displayed non-volatile binary WORM memory behavior with ON/OFF ratios up to 10⁴, low threshold voltages as low as -1.52 V, and substantial stability over 100 cycles with retention time of 4000s. Notably, asymmetric compounds containing triphenylamine donor exhibited superior memory performance. Density functional theory studies further validated the proposed charge transfer and charge trapping mechanism. These results establish dibenzothiophene sulfone-based donor-acceptor systems as promising candidates for next-generation organic memory technologies.