Nitrogen doped carbon dots embedded in poly(ionic liquid) as high efficient metal-free electrocatalyst for oxygen reduction reaction

Seeking for highly efficient and cost-effective catalysts towards electrochemical activation of small molecules is the key process in the development of renewable technologies. In this work the ionic liquid has been proposed as a promising candidate for elaborating of hybrid materials for multi-purposes in the fields of electrocatalysis. Precisely, the polymer brushes based ionic liquid, poly(imidazolium), were used as a platform for host guesting carbon-dots material and their electrocatalytic activity towards the oxygen reduction reaction was evaluated. The obtained results demonstrate that the presence of the poly(IL) shifts the ORR performance over carbon dots from 2 electron pathway, with hydrogen peroxide as the main product, to nearly 4 electron pathway. Thus, a switch from hydrogen peroxide generation (> 80%) to water production is obtained in the presence of the poly (IL) layer over a broad potential range. This synergetic effect is correlated to the chemical structure and the morphology of the immobilized polymer ionic liquid. Finally, the poly(IL) was demonstrated to be a powerful strategy for boosting the catalytic activity for a given carbon-dots catalyst towards efficient 4 electron ORR.