Reconfigurable multifunctional neuromorphic memristor fabricated from two-dimensional ReSe2 ferroelectric nanosheet films

Memristor-based neuromorphic computing is beneficial for artificial intelligence to process external information autonomously with high speed and high efficiency. Two-dimensional (2D) layered van der Waals rhenium selenide (ReSe2) has optoelectronic and semiconductor properties, but its ferroelectricity has not been confirmed fully experimentally and the application exploration is currently limited. Here, we experimentally confirmed the room-temperature ferroelectricity of 2D ReSe2 and proposed a reconfigurable ReSe2 memristor that can realize multiple functions. The device can realize the conductance bidirectional regulation, and under the action of electrical signals, it exhibits the high 0.99 and 0.98 linearity and accurate bidirectional update of weights. Under the complementary effect of ReSe2 ferroelectric polarization flipping and interface defects, the device exhibits the memcapacitor and memristor reconfigurable behavior and multiple functions such as visible light perception, logical “OR” calculation, and long/short-term synaptic plasticity. In addition, the six-layer convolutional neural network built based on ReSe2 memristors can perform feature extraction and classification recognition of handwritten digital pictures, and its recognition accuracy can reach 97.04%. In addition to obtain substantial experimental evidence for the ferroelectricity of 2D ReSe2, this work also provides a new avenue for the implementation of ReSe2 ferroelectric memristors in the neuromorphic computing system with the front-end sensing and back-end processing.