Flexible Memristive Organic Solar Cell Using Multilayer 2D Titanium Carbide MXene Electrodes

Adv Sci (Weinh). 2023 Jul;10(19):e2300433. doi: 10.1002/advs.202300433. Epub 2023 May 3.

Abstract

Hybrid systems have attracted significant attention within the scientific community due to their multifunctionality, which has resulted in increasing demands for wearable electronics, green energy, and miniaturization. Furthermore, MXenes are promising two-dimensional materials that have been applied in various areas due to their unique properties. Herein, a flexible, transparent, and conductive electrode (FTCE) based on a multilayer hybrid MXene/Ag/MXene structure that can be applied to realize an inverted organic solar cell (OSC) with memory and learning functionalities is reported. This optimized FTCE exhibits high transmittance (84%), low sheet resistance (9.7 Ω sq-1 ), and reliable operation (even after 2000 bending cycles). Moreover, the OSC using this FTCE achieves a power conversion efficiency of 13.86% and sustained photovoltaic performance, even after hundreds of switching cycles. The fabricated memristive OSC (MemOSC) device also exhibits reliable resistive switching behavior at low operating voltages of 0.60 and -0.33 V (similar to biological synapses), an excellent ON/OFF ratio (103 ), stable endurance performance (4 × 103 ), and memory retention properties (104 s). Moreover, the MemOSC device can mimic synaptic functionalities on a biological time scale. Thus, MXene can potentially be used as an electrode for highly efficient OSCs with memristive functions for future intelligent solar cell modules.

Keywords: Ti3C2Tx MXene; flexible organic solar cells; flexible transparent electrodes; memristors; neuromorphic computing.