Covalent Functionalization of Black Phosphorus with Conjugated Polymer for Information Storage

Abstract Major disadvantages of black phosphorus (BP) are its poor air‐stability and poor solubility in common organic solvents. The best way to solve this problem is to incorporate BP into a polymer backbone or a polymer matrix to form novel functional materials that can provide both challenges and opportunities for new innovation in optoelectronic and photonic applications. As a proof‐of concept application, we synthesized in situ the first highly soluble conjugated polymer‐covalently functionalized BP derivative (PDDF‐ g ‐BP) which was used to fabricate a resistive random access memory (RRAM) device with a configuration of Au/PDDF‐ g ‐BP/ITO. In contrast to PDDF without memory effect, PDDF‐ g ‐BP‐based device exhibits a nonvolatile rewritable memory performance, with a turn‐on and turn‐off voltages of +1.95 V and −2.34 V, and an ON/OFF current ratio of 10 4 . The current through the device in both the ON and OFF states is still kept unchanged even at 200th switching cycle. The PDDF/BP blends show a very unstable memory performance with a very small ON/OFF current ratio.