Advances in Interfacial Electrostatic Energy Harvesting via Direct Current Triboelectric Nanogenerators

Abstract Interfacial electrostatic energy, widely presents in natural and artificial environments, has long been regarded as a hazardous and uncontrollable energy form due to its erratic discharge behavior. The advent of direct current triboelectric nanogenerators (DC‐TENGs) has opened new approaches for effectively harvesting electrostatic energy during electrostatic discharges and generating unidirectional current outputs without external rectifiers. Compared with conventional alternating current TENGs, DC‐TENGs offer simplified circuit design, and better adaptability for directly driving electronic devices. This review provides a comprehensive summary of the fundamental mechanisms of DC‐TENGs, including air breakdown‐based charge transfer and structural innovations that enable continuous DC output. The key factors affecting performance are systematically analyzed, such as material selection, structural configuration, and environmental conditions, along with recent strategies for performance enhancement. Furthermore, the versatility of DC‐TENGs is highlighted through their wide‐ranging applications in high‐voltage power generation, micro/nano energy sources, wearable electronics, self‐powered sensors, and ocean wave energy harvesting. This review concludes with perspectives on future research directions and practical deployment, emphasizing the potential of DC‐TENGs in enabling sustainable, distributed energy systems for smart environments and next‐generation electronics.