Self‐Powered Infrared‐Detectable BP/Ta₂NiS₅ Heterojunction and Its Application in Energy‐Efficient Optoelectronic Synapses

Abstract

The development of energy‐efficient and high‐performance optoelectronic devices is crucial for the advancement of modern optoelectronic and microelectronic systems. Although the self‐powered devices and optoelectronic synapses based on 2D heterojunction show great application prospects, the high energy consumption and infrared band detection of self‐powered optoelectronic synapses are still an urgent problem to be solved. In this report, a BP/Ta2NiS5 heterojunction is constructed to achieve infrared detection by leveraging differences in Fermi energy levels. This heterojunction exhibits a high specific detectivity of 6.57 × 1010, 2.6 × 1010, and 1.12 × 1010 Jones and responsivity of 20, 10.6, and 5.9 mA W−1 for 1064, 1550, and 2200 nm infrared light at 0 bias voltage, respectively. In addition, under the 2200 nm light, by applying an ultra‐low bias voltage of 800 µV, the heterojunction exhibits ultra‐low power and energy consumption of 28.8 pW and 0.64 pJ, successfully simulates a variety of synaptic behaviors under infrared light, and demonstrates its image perception and image memory capabilities. These findings position the BP/Ta2NiS5 heterojunction as an ideal candidate for a multifunctional optoelectronic device crucial for advanced photodetection, neuromorphic computing, and artificial intelligence.