Nanocomposite Materials for Eco-Friendly Tribo- and Piezoelectric Nanogenerators

Circularity and sustainability of energy devices are gaining importance in the face of growing global energy demand, which enlarges the electronics waste as well as increases the scarcity of critical energy materials. Triboelectric nanogenerators (TENG), which have a great potential in providing renewable energy, often lack sustainability themselves as the constituting materials are mostly petrol-based, fluorinated polymers and metals.^1,2 Therefore, revalorized biomass like lignocellulosics and agri-food residues are increasingly considered as triboactive components.³ Similar concerns surround piezoelectric nanogenerators (PENG), where lead-free inorganic materials and natural polymers are sought as new sustainable components of PENGs.⁴<br/>Here, we present preliminary results of eco-friendly nanogenerators based on different bionanocomposites. Biopolymers like cellulose, keratin, lignin, chitosan and alginate are investigated both as coating and matrix with different fillers such as nanocarbons and barium titanate (BTO) particles in order to tune the triboelectric and piezoelectric properties. In addition, the role of porosity is a further parameter under investigation both for the electrical output and complementary properties. Herein, carbon fiber assemblies and brushes are also explored as substrates for the construction of 3-dimensional triboactive elements. Finally, contact-separation and single-electrode nanogenerators are constructed and tested for different insulation and harvesting applications.<br/><br/><br/>References:<br/>1. C. Wu, A. C. Wang, W. Ding, H. Guo, Z. L. Wang. <i>Adv. Energy Mater. </i><b>2019</b><i>, </i>9, 1802906.<br/>2. B. Chen, Y. Yang, Z. L. Wang,. <i>Adv. Energy Mater. </i><b>2018</b>, 8<b>, </b>1.<br/>3. L. Cao, X. Qiu, Q. Jiao, P. Zhao, J. Li, Y. Wei, <i>Intern. J. Biol. Macromol. </i><b>2021</b>, 173, 225<i>.</i><br/>4. Su et al., <i>ACS Nano</i> <b>2020</b>, 14, 14665.