Sustainable production of carbon nanomaterials based on TPT backsheet pyrolysis from end-of-life photovoltaic modules

Abstract

The environmentally friendly recycling of end-of-life (EoL) photovoltaic modules is a crucial pathway to achieving “carbon neutrality.” However, currently, most efforts are primarily focused on the recovery of valuable metals, neglecting the utilization of TPT (Tedlar/PET/Tedlar) plastic backsheet. This work develops a two-stage pyrolysis process for TPT decomposition and which can convert into high-value nanocarbon materials and hydrogen under the catalysis of Ni and Fe nanometal particles. The pyrolysis behavior of TPT backplates was systematically investigated, the gas chromatography results reveal that the pyrolysis products primarily consisted of CO2, CO, CH4, CH3CHO, and other small molecules, alongside sizeable residual compounds under the catalytic degradation process. The resulting hydrocarbons play an important role as carbon sources in the formation of carbon nanomaterials and hydrogen generation. The study thoroughly discusses the effects of different catalyst on pyrolysis gas species and components, fixed carbon content, and nanocarbon morphology. Molecular dynamics simulations based on the reactive force field (ReaxFF) was performed to analyze the pyrolysis products. Finally, a gas–liquid-solid physical model was proposed to interpret the growth process of the carbon nanomaterials under Ni-Fe nanometallic catalysis.