Sustainable Organic Polymer Solar Cells Using TiO2 Derived From Automobile Paint Sludge

We demonstrate green synthesis of TiO

2

nanoparticles (Nps) derived from automobile paint sludge (APG) and its application in the development of sustainable and solution processable polymer solar cells (PSCs). The APG contains TiO

2

> 35 % of its weight with several surfactants, organic polymers and ~ 2 to 10 % inorganic matter depending on the type of paints used. The TiO

2

is generally present as micro sized particles in the APG which on hydrothermal treatment transform into nano sized particles. These organic matter is thermally extracted by a specially designed reaction vessel, where as the inorganic impurities are removed by repeated washing with dilute acids and bases. The TiO

2

Nps are characterized by SEM imaging, EDX analysis, powder XRD, TG/DTA and FTIR, spectroscopy techniques. The TiO

2

Nps are re-suspended in methanol for application in PSCs as an efficient electron transport layer. The TiO

2

layer was spin coated on bulk hetero junction active layer of low band gap donor polymers P3HT with PCBM as electron acceptor. The performance of the TiO

2

Nps is analyzed by fabricating devices in ITO/PEDOT:PSS/active layer/TiO

2

/Al configuration. The present work has implication for ultra low cost and sustainable PSCs with advantage of recycling of a highly hazardous industrial waste.