Why are Schottky diodes preferred in low-voltage TENG rectification?

Schottky diodes are preferred in low-voltage TENG rectification because they have a lower forward voltage drop compared to traditional silicon diodes. The forward voltage drop is the minimum voltage required for a diode to start conducting current. TENGs often generate relatively low voltages, especially under low-frequency or low-amplitude mechanical excitation. If the forward voltage drop of the diodes in a rectifier is too high, a significant portion of the TENG's output voltage will be lost, reducing the overall rectification efficiency. Schottky diodes, with their lower forward voltage drop (typically around 0.15 to 0.45 V), allow for more efficient rectification of these low-voltage signals. This results in a higher DC output voltage and improved energy harvesting efficiency. For example, if a TENG generates a peak voltage of 0.5 V, using a silicon diode with a forward voltage drop of 0.7 V would result in no current flow. However, a Schottky diode with a 0.2 V drop would allow for rectification and energy harvesting. In short, using Schottky diodes minimizes voltage losses and maximizes the energy extracted from the TENG, particularly in low-voltage applications.