Touch-modulated van der Waals heterostructure with self-writing power switch for synaptic simulation

Neuromorphic electronics with two-dimensional van der Waals materials meet the ever-increasing demands of both the semiconductor industry and biological engineering, such as miniaturization, structure flexibility, multifunctionality, and low power consumption. However, the majority of reported electronic devices achieve multifarious memory storage states or synaptic plasticity through regulation of an electrical or an optical signal. Herein, we propose an innovative touch-modulated device based on an indium selenide/hexagonal boron nitride/graphene van der Waals heterostructure coupled with a triboelectric nanogenerator. The device is prepared utilizing a simple copper grid shadow mask instead of the expensive and cumbersome electron beam lithography process, exhibits high mobility of 829 cm² V⁻¹ s⁻¹, low voltage, and low power consumption. Nonvolatile memory with self-writing power, durability and multibit data storage is achieved through mechanical modulation without an additional gate-voltage supply. Moreover, by adjusting the distance between the two friction layers, essential synaptic plasticity, including short-term and long-term potentiation/depression and paired-pulse facilitation/depression, are successfully imitated in the device. Most importantly, we achieve ultralow power consumption of 165 aJ in tribotronic synapses owing to the ultra-high mobility of InSe. Our tribotronic synapse with self-writing power has great potential to simulate the low-power-consuming neuromorphic bioelectronic devices with multiple functions and lays the foundation for future advanced neuromorphic systems and artificial intelligence.