A freestanding rotating triboelectric nanogenerator with large area and high efficiency for triboelectric plasma CO2 reduction

Fabrication of a large-scale, high-performance, high stability cylinder freestanding rotating triboelectric nanogenerator (FR-TENG) for mechanical-energy-driven CO2 reduction is a bottleneck to be overcome. Herein, from the reasonable geometric structure and triboelectric materials, a cylinder-type, large-area, high-stability, and soft-contact FR-TENG with superior output performance was well-constructed. At the optimal conditions, the maximum short-circuit current of FR-TENG is 35.1 μA, the maximum transferred triboelectric charge is 350 nC, and the conversion efficiency from mechanical to electrical energy is up to 16.7 %, which outperforms previously reported results under similar conditions. Applying it into triboelectric plasma reduction of CO2 system, the evolution rates of CO and O2 are 8.50 and 4.33 μmol h−1, respectively, and the conversion efficiency from mechanical to chemical energy is 1.84 %, which is better than most of the previous benchmark results in TENG driven-CO2 reduction systems. Finally, this device is applied to field experiments, and the generation rates of CO and O2 are obtained to be 5.06 and 2.33 μmol h−1 at a wind speed of 2.3 m s−1, respectively, with a maximum energy conversion efficiency of 0.72 %. This work provides a promising strategy for CO2 reduction systems driven by mechanical energy.