Multi-Stage buck strategy for power management of triboelectric nanogenerators

Triboelectric nanogenerators (TENGs) offer transformative potential for self-powered systems, yet their real-world applicability faces a key bottleneck as their performance and efficiency suffer dramatic degradation below 5 V that the operational threshold for most electronics when integrated with conventional power management circuits. Here, we overcome this limitation through the multi-stage buck strategy that synergistically combines dual-stage voltage conversion circuit with TENG's output characteristic by the Q-V curve, enabling precise voltage regulation at critical nodes. The strategy achieves approximately 80% circuit efficiency at the low-voltage range, with 90.9% in the primary circuit and 93.9% in the secondary circuit. Concurrently, the current and power density reach 5.19 A/m² and 9.70 W/m² at 1.87 V, which is nearly an order of magnitude improvement over best prior work. Demonstrated in self-powered hydrogen production system, this approach achieves a record gas yield of 16.5 mL/(min·m²), resolving the challenge of low-voltage inefficiency in self-powered systems. Additionally, it is capable of powering a mobile phone. Our work establishes a foundational framework for implementing efficient TENG-powered devices in Internet of Things networks and industrial applications, bridging the gap between energy harvesting technologies and actual energy demands.