Environmental lifecycle assessment of CO-filled triboelectric nanogenerators to help achieve carbon neutrality

Industrialization activities in recent decades have achieved an unprecedentedly prosperous civilization. Nevertheless, energy-shortage crises and environmental problems have increased. In particular, the exacerbated greenhouse effect and global warming caused by the sharp rise of carbon dioxide (CO 2 ) levels in the atmosphere cause threats and challenges to the living environment, thereby making the vision of carbon neutrality our immediate need. Triboelectric nanogenerators (TENGs) can harvest very small amounts of mechanical energy from the surrounding environment and convert it into electrical energy, thereby providing a new avenue for energy architectures. Taking advantage of the simple structure, low cost, and high energy density of TENGs, this work proposes a method to inflate CO 2 gas into TENGs for energy-harvesting of ocean waves to minimize the carbon footprint. Analysis of lifecycle assessment showed that the CO 2 emissions generated by this scheme were minimal, and that the generated electricity could provide clean energy to compensate for CO 2 emissions and, ultimately, achieve negative carbon emission. This research may provide a pathway for applying TENGs in green-energy harvesting and attaining the sustainable development goals set by United Nations and carbon neutrality. CO 2 pumped into nanogenerators in ocean for wave energy collection can offset carbon emissions, producing eco-friendly energy. LCA shows that the production of 1 kW of electricity emits approximately 42 g of carbon dioxide, which is comparable to traditional wind energy.