Recently, electrochemical capacitors (ECs) have attracted consideration as AC line filter capacitors to replace the current aluminum electrolytic capacitors (AECs), which is an important direction of circuit integration miniaturization. In this work, a simple one-step hydrothermal method without additives was used to prepare vertically oriented NiTe₂ nanosheets on nickel foam, which provides large surface area and fast charge transport. The NiTe₂ ECs exhibit true pseudocapacitive nature, stable rate capability, efficient charge transport and high cyclic stability. In addition, they also deliver a super high specific area capacitance of 846.47 μF cm⁻² at 120 Hz, while retaining small resistor-capacitor (RC) time constant of 1.01 ms and large negative phase angle of 52.7°, indicating its excellent filtering performance. As expected, the NiTe₂ ECs perform evidently better filtering effect than commercial AECs when used as filter capacitors in circuits. From a practical point of view, we applied the NiTe₂ filter capacitor to regulate the triboelectric nanogenerator (TENG) output, successfully supplying a light-emitting diode (LED) in a steady state. The NiTe₂ filter capacitor proposed in this work can be fully used as a large-capacitance, small-size filter capacitor for portable devices and also applied to actual AC line circuits in the future.

近年来，电化学电容器（EC）作为交流线路滤波电容器来代替当前的铝电解电容器（AEC）备受关注，这是电路集成小型化的重要方向。在这项工作中，使用一种简单的无添加剂的一步水热法在镍泡沫上制备了垂直取向的NiTe ₂纳米片，从而提供了大的表面积和快速的电荷传输。NiTe ₂ EC具有真正的伪电容性质，稳定的速率能力，有效的电荷传输和高循环稳定性。此外，它们还提供了846.47μFcm ^-2的超高比面积电容在120 Hz频率下，同时保持小的电阻电容（RC）时间常数1.01 ms和大的负相角52.7°，表明其出色的滤波性能。不出所料，当用作电路中的滤波电容器时，NiTe ₂ EC的滤波效果明显好于商用AEC。从实际的角度来看，我们应用NiTe ₂滤波电容器来调节摩擦电纳米发电机（TENG）的输出，从而成功地提供了稳定状态的发光二极管（LED）。这项工作中提出的NiTe ₂滤波电容器可以完全用作便携式设备的大容量，小尺寸的滤波电容器，并且将来也可以应用于实际的交流线路中。