Natively oxidized 2D NbSe2 enables ultralow-power electrical switching†

In the context of the burgeoning information technology industry, the exponential growth in data storage and processing requirements has become increasingly evident. Threshold switching devices stand out as a pioneering solution with enhanced speed, superior integration, and lower energy consumption, marking a significant stride in technological progress. However, the development of these devices is limited by their relatively large leakage current, poor cyclic uniformity, and low endurance. Herein, we introduce a novel threshold switching device with low energy consumption, fairly high uniformity and endurance based on the native oxidized 2D NbSe₂ material, where the oxidation product is Nb₂O₅. This oxide exhibits high resistivity to further reduce the leakage current. As a result, the two-terminal NbSe₂/Nb₂O₅ device exhibits excellent threshold switching performance with low leakage current (∼10 fA) and low operating current (600 fA), which enables ultralow energy consumption (0.63 aJ) and high endurance (10⁶) compared with other 2D materials. Our work offers a new approach for reducing the leakage current of the threshold switching device, thereby paving the way for its applications in data storage and brain-inspired computing.